package diagnostics;=head1 NAMEdiagnostics - Perl compiler pragma to force verbose warning diagnosticssplain - standalone program to do the same thing=head1 SYNOPSISAs a pragma:    use diagnostics;    use diagnostics -verbose;    enable  diagnostics;    disable diagnostics;Aa a program:    perl program 2>diag.out    splain [-v] [-p] diag.out=head1 DESCRIPTION=head2 The C<diagnostics> PragmaThis module extends the terse diagnostics normally emitted by both theperl compiler and the perl interpeter, augmenting them with the moreexplicative and endearing descriptions found in L<perldiag>.  Like theother pragmata, it affects the compilation phase of your program ratherthan merely the execution phase.To use in your program as a pragma, merely invoke    use diagnostics;at the start (or near the start) of your program.  (Note that this I<does> enable perl's B<-w> flag.)  Your wholecompilation will then be subject(ed :-) to the enhanced diagnostics.These still go out B<STDERR>.Due to the interaction between runtime and compiletime issues,and because it's probably not a very good idea anyway,you may not use C<no diagnostics> to turn them off at compiletime.However, you may control there behaviour at runtime using the disable() and enable() methods to turn them off and on respectively.The B<-verbose> flag first prints out the L<perldiag> introduction beforeany other diagnostics.  The $diagnostics::PRETTY variable can generate nicerescape sequences for pagers.=head2 The I<splain> ProgramWhile apparently a whole nuther program, I<splain> is actually nothingmore than a link to the (executable) F<diagnostics.pm> module, as well asa link to the F<diagnostics.pod> documentation.  The B<-v> flag is likethe C<use diagnostics -verbose> directive.The B<-p> flag is like the$diagnostics::PRETTY variable.  Since you're post-processing with I<splain>, there's no sense in being able to enable() or disable() processing.Output from I<splain> is directed to B<STDOUT>, unlike the pragma.=head1 EXAMPLESThe following file is certain to trigger a few errors at bothruntime and compiletime:    use diagnostics;    print NOWHERE "nothing\n";    print STDERR "\n\tThis message should be unadorned.\n";    warn "\tThis is a user warning";    print "\nDIAGNOSTIC TESTER: Please enter a <CR> here: ";    my $a, $b = scalar <STDIN>;    print "\n";    print $x/$y;If you prefer to run your program first and look at its problemafterwards, do this:    perl -w test.pl 2>test.out    ./splain < test.outNote that this is not in general possible in shells of more dubious heritage, as the theoretical     (perl -w test.pl >/dev/tty) >& test.out    ./splain < test.outBecause you just moved the existing B<stdout> to somewhere else.If you don't want to modify your source code, but still have on-the-flywarnings, do this:    exec 3>&1; perl -w test.pl 2>&1 1>&3 3>&- | splain 1>&2 3>&- Nifty, eh?If you want to control warnings on the fly, do something like this.Make sure you do the C<use> first, or you won't be able to getat the enable() or disable() methods.    use diagnostics; # checks entire compilation phase 	print "\ntime for 1st bogus diags: SQUAWKINGS\n";	print BOGUS1 'nada';	print "done with 1st bogus\n";    disable diagnostics; # only turns off runtime warnings	print "\ntime for 2nd bogus: (squelched)\n";	print BOGUS2 'nada';	print "done with 2nd bogus\n";    enable diagnostics; # turns back on runtime warnings	print "\ntime for 3rd bogus: SQUAWKINGS\n";	print BOGUS3 'nada';	print "done with 3rd bogus\n";    disable diagnostics;	print "\ntime for 4th bogus: (squelched)\n";	print BOGUS4 'nada';	print "done with 4th bogus\n";=head1 INTERNALSDiagnostic messages derive from the F<perldiag.pod> file when available atruntime.  Otherwise, they may be embedded in the file itself when thesplain package is built.   See the F<Makefile> for details.If an extant $SIG{__WARN__} handler is discovered, it will continueto be honored, but only after the diagnostics::splainthis() function (the module's $SIG{__WARN__} interceptor) has had its way with yourwarnings.There is a $diagnostics::DEBUG variable you may set if you're desperatelycurious what sorts of things are being intercepted.    BEGIN { $diagnostics::DEBUG = 1 } =head1 BUGSNot being able to say "no diagnostics" is annoying, but may not beinsurmountable.The C<-pretty> directive is called too late to affect matters.You have to do this instead, and I<before> you load the module.    BEGIN { $diagnostics::PRETTY = 1 } I could start up faster by delaying compilation until it should beneeded, but this gets a "panic: top_level" when using the pragma formin Perl 5.001e.While it's true that this documentation is somewhat subserious, if you usea program named I<splain>, you should expect a bit of whimsy.=head1 AUTHORTom Christiansen <F<tchrist@mox.perl.com>>, 25 June 1995.=cutrequire 5.001;use Carp;use Config;($privlib, $archlib) = @Config{qw(privlibexp archlibexp)};if ($^O eq 'VMS') {    require VMS::Filespec;    $privlib = VMS::Filespec::unixify($privlib);    $archlib = VMS::Filespec::unixify($archlib);}@trypod = ("$archlib/pod/perldiag.pod",	   "$privlib/pod/perldiag-$].pod",	   "$privlib/pod/perldiag.pod");($PODFILE) = ((grep { -e } @trypod), $trypod[$#trypod])[0];$DEBUG ||= 0;my $WHOAMI = ref bless [];  # nobody's business, prolly not even mine$| = 1;local $_;CONFIG: {    $opt_p = $opt_d = $opt_v = $opt_f = '';    %HTML_2_Troff = %HTML_2_Latin_1 = %HTML_2_ASCII_7 = ();      %exact_duplicate = ();    unless (caller) { 	$standalone++;	require Getopt::Std;	Getopt::Std::getopts('pdvf:')	    or die "Usage: $0 [-v] [-p] [-f splainpod]";	$PODFILE = $opt_f if $opt_f;	$DEBUG = 2 if $opt_d;	$VERBOSE = $opt_v;	$PRETTY = $opt_p;    }     if (open(POD_DIAG, $PODFILE)) {	warn "Happy happy podfile from real $PODFILE\n" if $DEBUG;	last CONFIG;    }     if (caller) {	INCPATH: {	    if ($^O eq 'MacOS') {	    	for $file ( (map { /:$/ ? "$_$WHOAMI.pm" : "$_:$WHOAMI.pm" } @INC), $0) {		    warn "Checking $file\n" if $DEBUG;		    if (open(POD_DIAG, $file)) {		    	while (<POD_DIAG>) {			    next unless /^__END__\s*# wish diag dbase were more accessible/;			    print STDERR "podfile is $file\n" if $DEBUG;			    last INCPATH;			}		    }		}	    } else {	    	for $file ( (map { "$_/$WHOAMI.pm" } @INC), $0) {		    warn "Checking $file\n" if $DEBUG;		    if (open(POD_DIAG, $file)) {		    	while (<POD_DIAG>) {			    next unless /^__END__\s*# wish diag dbase were more accessible/;			    print STDERR "podfile is $file\n" if $DEBUG;			    last INCPATH;			}		    }		}	    }	}    } else { 	print STDERR "podfile is <DATA>\n" if $DEBUG;	*POD_DIAG = *main::DATA;    }}if (eof(POD_DIAG)) {     die "couldn't find diagnostic data in $PODFILE @INC $0";}%HTML_2_Troff = (    'amp'	=>	'&',	#   ampersand    'lt'	=>	'<',	#   left chevron, less-than    'gt'	=>	'>',	#   right chevron, greater-than    'quot'	=>	'"',	#   double quote    "Aacute"	=>	"A\\*'",	#   capital A, acute accent    # etc);%HTML_2_Latin_1 = (    'amp'	=>	'&',	#   ampersand    'lt'	=>	'<',	#   left chevron, less-than    'gt'	=>	'>',	#   right chevron, greater-than    'quot'	=>	'"',	#   double quote    "Aacute"	=>	"\xC1"	#   capital A, acute accent    # etc);%HTML_2_ASCII_7 = (    'amp'	=>	'&',	#   ampersand    'lt'	=>	'<',	#   left chevron, less-than    'gt'	=>	'>',	#   right chevron, greater-than    'quot'	=>	'"',	#   double quote    "Aacute"	=>	"A"	#   capital A, acute accent    # etc);*HTML_Escapes = do {    if ($standalone) {	$PRETTY ? \%HTML_2_Latin_1 : \%HTML_2_ASCII_7;     } else {	\%HTML_2_Latin_1;     }}; *THITHER = $standalone ? *STDOUT : *STDERR;$transmo = <<EOFUNC;sub transmo {    local \$^W = 0;  # recursive warnings we do NOT need!    study;EOFUNC### sub finish_compilation {  # 5.001e panic: top_level for embedded version    print STDERR "FINISHING COMPILATION for $_\n" if $DEBUG;    ### local     $RS = '';    local $_;    while (<POD_DIAG>) {	#s/(.*)\n//;	#$header = $1;	unescape();	if ($PRETTY) {	    sub noop   { return $_[0] }  # spensive for a noop	    sub bold   { my $str =$_[0];  $str =~ s/(.)/$1\b$1/g; return $str; } 	    sub italic { my $str = $_[0]; $str =~ s/(.)/_\b$1/g;  return $str; } 	    s/[BC]<(.*?)>/bold($1)/ges;	    s/[LIF]<(.*?)>/italic($1)/ges;	} else {	    s/[BC]<(.*?)>/$1/gs;	    s/[LIF]<(.*?)>/$1/gs;	} 	unless (/^=/) {	    if (defined $header) { 		if ( $header eq 'DESCRIPTION' && 		    (   /Optional warnings are enabled/ 		     || /Some of these messages are generic./		    ) )		{		    next;		} 		s/^/    /gm;		$msg{$header} .= $_;	    }	    next;	} 	unless ( s/=item (.*)\s*\Z//) {	    if ( s/=head1\sDESCRIPTION//) {		$msg{$header = 'DESCRIPTION'} = '';	    }	    next;	}	# strip formatting directives in =item line	($header = $1) =~ s/[A-Z]<(.*?)>/$1/g;	if ($header =~ /%[sd]/) {	    $rhs = $lhs = $header;	    #if ($lhs =~ s/(.*?)%d(?!%d)(.*)/\Q$1\E\\d+\Q$2\E\$/g)  {	    if ($lhs =~ s/(.*?)%d(?!%d)(.*)/\Q$1\E\\d+\Q$2\E/g)  {		$lhs =~ s/\\%s/.*?/g;	    } else {		# if i had lookbehind negations, i wouldn't have to do this \377 noise		$lhs =~ s/(.*?)%s/\Q$1\E.*?\377/g;		#$lhs =~ s/\377([^\377]*)$/\Q$1\E\$/;		$lhs =~ s/\377([^\377]*)$/\Q$1\E/;		$lhs =~ s/\377//g;		$lhs =~ s/\.\*\?$/.*/; # Allow %s at the end to eat it all	    } 	    $transmo .= "    s{^$lhs}\n     {\Q$rhs\E}s\n\t&& return 1;\n";	} else {	    $transmo .= "    m{^\Q$header\E} && return 1;\n";	} 	print STDERR "$WHOAMI: Duplicate entry: \"$header\"\n"	    if $msg{$header};	$msg{$header} = '';    }     close POD_DIAG unless *main::DATA eq *POD_DIAG;    die "No diagnostics?" unless %msg;    $transmo .= "    return 0;\n}\n";    print STDERR $transmo if $DEBUG;    eval $transmo;    die $@ if $@;    $RS = "\n";### }if ($standalone) {    if (!@ARGV and -t STDIN) { print STDERR "$0: Reading from STDIN\n" }     while (defined ($error = <>)) {	splainthis($error) || print THITHER $error;    }     exit;} else {     $old_w = 0; $oldwarn = ''; $olddie = '';}sub import {    shift;    $old_w = $^W;    $^W = 1; # yup, clobbered the global variable; tough, if you	     # want diags, you want diags.    return if $SIG{__WARN__} eq \&warn_trap;    for (@_) {	/^-d(ebug)?$/ 	   	&& do {				    $DEBUG++;				    next;				   };	/^-v(erbose)?$/ 	&& do {				    $VERBOSE++;				    next;				   };	/^-p(retty)?$/ 		&& do {				    print STDERR "$0: I'm afraid it's too late for prettiness.\n";				    $PRETTY++;				    next;			       };	warn "Unknown flag: $_";    }     $oldwarn = $SIG{__WARN__};    $olddie = $SIG{__DIE__};    $SIG{__WARN__} = \&warn_trap;    $SIG{__DIE__} = \&death_trap;} sub enable { &import }sub disable {    shift;    $^W = $old_w;    return unless $SIG{__WARN__} eq \&warn_trap;    $SIG{__WARN__} = $oldwarn;    $SIG{__DIE__} = $olddie;} sub warn_trap {    my $warning = $_[0];    if (caller eq $WHOAMI or !splainthis($warning)) {	print STDERR $warning;    }     &$oldwarn if defined $oldwarn and $oldwarn and $oldwarn ne \&warn_trap;};sub death_trap {    my $exception = $_[0];    # See if we are coming from anywhere within an eval. If so we don't    # want to explain the exception because it's going to get caught.    my $in_eval = 0;    my $i = 0;    while (1) {      my $caller = (caller($i++))[3] or last;      if ($caller eq '(eval)') {	$in_eval = 1;	last;      }    }    splainthis($exception) unless $in_eval;    if (caller eq $WHOAMI) { print STDERR "INTERNAL EXCEPTION: $exception"; }     &$olddie if defined $olddie and $olddie and $olddie ne \&death_trap;    # We don't want to unset these if we're coming from an eval because    # then we've turned off diagnostics. (Actually what does this next    # line do?  -PSeibel)    $SIG{__DIE__} = $SIG{__WARN__} = '' unless $in_eval;    local($Carp::CarpLevel) = 1;    confess "Uncaught exception from user code:\n\t$exception";	# up we go; where we stop, nobody knows, but i think we die now	# but i'm deeply afraid of the &$olddie guy reraising and us getting	# into an indirect recursion loop};sub splainthis {    local $_ = shift;    local $\;    ### &finish_compilation unless %msg;    s/\.?\n+$//;    my $orig = $_;    # return unless defined;    if ($exact_duplicate{$_}++) {	return 1;    }     if ($^O eq 'MacOS') {        s/^# //gm;   	s/.?\s*\nFile \'(.*?)\'; Line (\d+)/ at $1 line $2/mi;    }    s/, <.*?> (?:line|chunk).*$//;    $real = s/(.*?) at .*? (?:line|chunk) \d+.*/$1/;    s/^\((.*)\)$/$1/;    return 0 unless &transmo;    $orig = shorten($orig);    if ($old_diag{$_}) {	autodescribe();	if ($^O eq 'MacOS') {	    print THITHER "$orig # (#$old_diag{$_})\n";	} else {	    print THITHER "$orig (#$old_diag{$_})\n";	}	$wantspace = 1;    } else {	autodescribe();	$old_diag{$_} = ++$count;	print THITHER "\n" if $wantspace;	$wantspace = 0;	if ($^O eq 'MacOS') {	    print THITHER "$orig # (#$old_diag{$_})\n";	} else {	    print THITHER "$orig (#$old_diag{$_})\n";	}	if ($msg{$_}) {	    print THITHER $msg{$_};	} else {	    if (0 and $standalone) { 		print THITHER "    **** Error #$old_diag{$_} ",			($real ? "is" : "appears to be"),			" an unknown diagnostic message.\n\n";	    }	    return 0;	}     }    return 1;} sub autodescribe {    if ($VERBOSE and not $count) {	print THITHER &{$PRETTY ? \&bold : \&noop}("DESCRIPTION OF DIAGNOSTICS"),		"\n$msg{DESCRIPTION}\n";    } } sub unescape {     s {            E<              ( [A-Za-z]+ )                   >       } {          do {                exists $HTML_Escapes{$1}                ? do { $HTML_Escapes{$1} }                : do {                    warn "Unknown escape: E<$1> in $_";                    "E<$1>";                }          }     }egx;}sub shorten {    my $line = $_[0];    if (length($line) > 79 and index($line, "\n") == -1) {	my $space_place = rindex($line, ' ', 79);	if ($space_place != -1) {	    substr($line, $space_place, 1) = "\n\t";	}     }     return $line;} # have to do this: RS isn't set until run time, but we're executing at compile time$RS = "\n";1 unless $standalone;  # or it'll complain about itself__END__ # wish diag dbase were more accessible=head1 NAMEperldiag - various Perl diagnostics=head1 DESCRIPTIONThese messages are classified as follows (listed in increasing order ofdesperation):    (W) A warning (optional).    (D) A deprecation (optional).    (S) A severe warning (mandatory).    (F) A fatal error (trappable).    (P) An internal error you should never see (trappable).    (X) A very fatal error (nontrappable).    (A) An alien error message (not generated by Perl).Optional warnings are enabled by using the B<-w> switch.  Warnings maybe captured by setting C<$SIG{__WARN__}> to a reference to a routine thatwill be called on each warning instead of printing it.  See L<perlvar>.Trappable errors may be trapped using the eval operator.  SeeL<perlfunc/eval>.Some of these messages are generic.  Spots that vary are denoted with a %s,just as in a printf format.  Note that some messages start with a %s!The symbols C<"%-?@> sort before the letters, while C<[> and C<\> sort after.=over 4=item "my" variable %s can't be in a package(F) Lexically scoped variables aren't in a package, so it doesn't make senseto try to declare one with a package qualifier on the front.  Use local()if you want to localize a package variable.=item "my" variable %s masks earlier declaration in same scope(S) A lexical variable has been redeclared in the same scope, effectivelyeliminating all access to the previous instance.  This is almost alwaysa typographical error.  Note that the earlier variable will still existuntil the end of the scope or until all closure referents to it aredestroyed.=item "no" not allowed in expression(F) The "no" keyword is recognized and executed at compile time, and returnsno useful value.  See L<perlmod>.=item "use" not allowed in expression(F) The "use" keyword is recognized and executed at compile time, and returnsno useful value.  See L<perlmod>.=item % may only be used in unpack(F) You can't pack a string by supplying a checksum, because thechecksumming process loses information, and you can't go the otherway.  See L<perlfunc/unpack>.=item %s (...) interpreted as function(W) You've run afoul of the rule that says that any list operator followedby parentheses turns into a function, with all the list operators argumentsfound inside the parentheses.  See L<perlop/Terms and List Operators (Leftward)>.=item %s argument is not a HASH element(F) The argument to exists() must be a hash element, such as    $foo{$bar}    $ref->[12]->{"susie"}=item %s argument is not a HASH element or slice(F) The argument to delete() must be either a hash element, such as    $foo{$bar}    $ref->[12]->{"susie"}or a hash slice, such as    @foo{$bar, $baz, $xyzzy}    @{$ref->[12]}{"susie", "queue"}=item %s did not return a true value(F) A required (or used) file must return a true value to indicate thatit compiled correctly and ran its initialization code correctly.  It'straditional to end such a file with a "1;", though any true value woulddo.  See L<perlfunc/require>.=item %s found where operator expected(S) The Perl lexer knows whether to expect a term or an operator.  If itsees what it knows to be a term when it was expecting to see an operator,it gives you this warning.  Usually it indicates that an operator ordelimiter was omitted, such as a semicolon.=item %s had compilation errors(F) The final summary message when a C<perl -c> fails.=item %s has too many errors(F) The parser has given up trying to parse the program after 10 errors.Further error messages would likely be uninformative.=item %s matches null string many times(W) The pattern you've specified would be an infinite loop if theregular expression engine didn't specifically check for that.  See L<perlre>.=item %s never introduced(S) The symbol in question was declared but somehow went out of scopebefore it could possibly have been used.=item %s syntax OK(F) The final summary message when a C<perl -c> succeeds.=item %s: Command not found(A) You've accidentally run your script through B<csh> insteadof Perl.  Check the #! line, or manually feed your script intoPerl yourself.=item %s: Expression syntax(A) You've accidentally run your script through B<csh> insteadof Perl.  Check the #! line, or manually feed your script intoPerl yourself.=item %s: Undefined variable(A) You've accidentally run your script through B<csh> insteadof Perl.  Check the #! line, or manually feed your script intoPerl yourself.=item %s: not found(A) You've accidentally run your script through the Bourne shellinstead of Perl.  Check the #! line, or manually feed your scriptinto Perl yourself.=item B<-P> not allowed for setuid/setgid script(F) The script would have to be opened by the C preprocessor by name,which provides a race condition that breaks security.=item C<-T> and C<-B> not implemented on filehandles(F) Perl can't peek at the stdio buffer of filehandles when it doesn'tknow about your kind of stdio.  You'll have to use a filename instead.=item 500 Server errorSee Server error.=item ?+* follows nothing in regexp(F) You started a regular expression with a quantifier.  Backslash itif you meant it literally.   See L<perlre>.=item @ outside of string(F) You had a pack template that specified an absolute position outsidethe string being unpacked.  See L<perlfunc/pack>.=item accept() on closed fd(W) You tried to do an accept on a closed socket.  Did you forget to checkthe return value of your socket() call?  See L<perlfunc/accept>.=item Allocation too large: %lx(X) You can't allocate more than 64K on an MS-DOS machine.=item Allocation too large(F) You can't allocate more than 2^31+"small amount" bytes.=item Applying %s to %s will act on scalar(%s)(W) The pattern match (//), substitution (s///), and translation (tr///)operators work on scalar values.  If you apply one of them to an arrayor a hash, it will convert the array or hash to a scalar value -- thelength of an array, or the population info of a hash -- and then work onthat scalar value.  This is probably not what you meant to do.  SeeL<perlfunc/grep> and L<perlfunc/map> for alternatives.=item Arg too short for msgsnd(F) msgsnd() requires a string at least as long as sizeof(long).=item Ambiguous use of %s resolved as %s(W)(S) You said something that may not be interpreted the wayyou thought.  Normally it's pretty easy to disambiguate it by supplyinga missing quote, operator, parenthesis pair or declaration.=item Args must match #! line(F) The setuid emulator requires that the arguments Perl was invokedwith match the arguments specified on the #! line.  Since some systemsimpose a one-argument limit on the #! line, try combining switches;for example, turn C<-w -U> into C<-wU>.=item Argument "%s" isn't numeric%s(W) The indicated string was fed as an argument to an operator thatexpected a numeric value instead.  If you're fortunate the messagewill identify which operator was so unfortunate.=item Array @%s missing the @ in argument %d of %s()(D) Really old Perl let you omit the @ on array names in some spots.  Thisis now heavily deprecated.=item assertion botched: %s(P) The malloc package that comes with Perl had an internal failure.=item Assertion failed: file "%s"(P) A general assertion failed.  The file in question must be examined.=item Assignment to both a list and a scalar(F) If you assign to a conditional operator, the 2nd and 3rd argumentsmust either both be scalars or both be lists.  Otherwise Perl won'tknow which context to supply to the right side.=item Attempt to free non-arena SV: 0x%lx(P) All SV objects are supposed to be allocated from arenas that willbe garbage collected on exit.  An SV was discovered to be outside anyof those arenas.=item Attempt to free nonexistent shared string(P) Perl maintains a reference counted internal table of strings tooptimize the storage and access of hash keys and other strings.  Thisindicates someone tried to decrement the reference count of a stringthat can no longer be found in the table.=item Attempt to free temp prematurely(W) Mortalized values are supposed to be freed by the free_tmps()routine.  This indicates that something else is freeing the SV beforethe free_tmps() routine gets a chance, which means that the free_tmps()routine will be freeing an unreferenced scalar when it does try to freeit.=item Attempt to free unreferenced glob pointers(P) The reference counts got screwed up on symbol aliases.=item Attempt to free unreferenced scalar(W) Perl went to decrement the reference count of a scalar to see if itwould go to 0, and discovered that it had already gone to 0 earlier,and should have been freed, and in fact, probably was freed.  Thiscould indicate that SvREFCNT_dec() was called too many times, or thatSvREFCNT_inc() was called too few times, or that the SV was mortalizedwhen it shouldn't have been, or that memory has been corrupted.=item Attempt to use reference as lvalue in substr(W) You supplied a reference as the first argument to substr() usedas an lvalue, which is pretty strange.  Perhaps you forgot todereference it first.  See L<perlfunc/substr>.=item Bad arg length for %s, is %d, should be %d(F) You passed a buffer of the wrong size to one of msgctl(), semctl() orshmctl().  In C parlance, the correct sizes are, respectively,S<sizeof(struct msqid_ds *)>, S<sizeof(struct semid_ds *)>, andS<sizeof(struct shmid_ds *)>.=item Bad filehandle: %s(F) A symbol was passed to something wanting a filehandle, but the symbolhas no filehandle associated with it.  Perhaps you didn't do an open(), ordid it in another package.=item Bad free() ignored(S) An internal routine called free() on something that had never beenmalloc()ed in the first place. Mandatory, but can be disabled bysetting environment variable C<PERL_BADFREE> to 1.This message can be quite often seen with DB_File on systems with"hard" dynamic linking, like C<AIX> and C<OS/2>. It is a bug ofC<Berkeley DB> which is left unnoticed if C<DB> uses I<forgiving>system malloc().=item Bad hash(P) One of the internal hash routines was passed a null HV pointer.=item Bad name after %s::(F) You started to name a symbol by using a package prefix, and then didn'tfinish the symbol.  In particular, you can't interpolate outside of quotes,so    $var = 'myvar';    $sym = mypack::$var;is not the same as    $var = 'myvar';    $sym = "mypack::$var";=item Bad symbol for array(P) An internal request asked to add an array entry to something thatwasn't a symbol table entry.=item Bad symbol for filehandle(P) An internal request asked to add a filehandle entry to something thatwasn't a symbol table entry.=item Bad symbol for hash(P) An internal request asked to add a hash entry to something thatwasn't a symbol table entry.=item Badly placed ()'s(A) You've accidentally run your script through B<csh> insteadof Perl.  Check the #! line, or manually feed your script intoPerl yourself.=item Bareword "%s" not allowed while "strict subs" in use(F) With "strict subs" in use, a bareword is only allowed as asubroutine identifier, in curly braces or to the left of the "=>" symbol.Perhaps you need to predeclare a subroutine?=item BEGIN failed--compilation aborted(F) An untrapped exception was raised while executing a BEGIN subroutine.Compilation stops immediately and the interpreter is exited.=item BEGIN not safe after errors--compilation aborted(F) Perl found a C<BEGIN {}> subroutine (or a C<use> directive, whichimplies a C<BEGIN {}>) after one or more compilation errors hadalready occurred.  Since the intended environment for the C<BEGIN {}>could not be guaranteed (due to the errors), and since subsequent codelikely depends on its correct operation, Perl just gave up.=item bind() on closed fd(W) You tried to do a bind on a closed socket.  Did you forget to checkthe return value of your socket() call?  See L<perlfunc/bind>.=item Bizarre copy of %s in %s(P) Perl detected an attempt to copy an internal value that is not copiable.=item Callback called exit(F) A subroutine invoked from an external package via perl_call_sv()exited by calling exit.=item Can't "goto" outside a block(F) A "goto" statement was executed to jump out of what might looklike a block, except that it isn't a proper block.  This usuallyoccurs if you tried to jump out of a sort() block or subroutine, whichis a no-no.  See L<perlfunc/goto>.=item Can't "last" outside a block(F) A "last" statement was executed to break out of the current block,except that there's this itty bitty problem called there isn't acurrent block.  Note that an "if" or "else" block doesn't count as a"loopish" block, as doesn't a block given to sort().  You can usually doublethe curlies to get the same effect though, because the inner curlieswill be considered a block that loops once.  See L<perlfunc/last>.=item Can't "next" outside a block(F) A "next" statement was executed to reiterate the current block, butthere isn't a current block.  Note that an "if" or "else" block doesn'tcount as a "loopish" block, as doesn't a block given to sort().  You canusually double the curlies to get the same effect though, because the innercurlies will be considered a block that loops once.  See L<perlfunc/next>.=item Can't "redo" outside a block(F) A "redo" statement was executed to restart the current block, butthere isn't a current block.  Note that an "if" or "else" block doesn'tcount as a "loopish" block, as doesn't a block given to sort().  You canusually double the curlies to get the same effect though, because the innercurlies will be considered a block that loops once.  See L<perlfunc/redo>.=item Can't bless non-reference value(F) Only hard references may be blessed.  This is how Perl "enforces"encapsulation of objects.  See L<perlobj>.=item Can't break at that line(S) A warning intended to only be printed while running within the debugger, indicatingthe line number specified wasn't the location of a statement that couldbe stopped at.=item Can't call method "%s" in empty package "%s"(F) You called a method correctly, and it correctly indicated a packagefunctioning as a class, but that package doesn't have ANYTHING definedin it, let alone methods.  See L<perlobj>.=item Can't call method "%s" on unblessed reference(F) A method call must know in what package it's supposed to run.  Itordinarily finds this out from the object reference you supply, butyou didn't supply an object reference in this case.  A reference isn'tan object reference until it has been blessed.  See L<perlobj>.=item Can't call method "%s" without a package or object reference(F) You used the syntax of a method call, but the slot filled by theobject reference or package name contains an expression that returnsneither an object reference nor a package name.  (Perhaps it's null?)Something like this will reproduce the error:    $BADREF = undef;    process $BADREF 1,2,3;    $BADREF->process(1,2,3);=item Can't chdir to %s(F) You called C<perl -x/foo/bar>, but C</foo/bar> is not a directorythat you can chdir to, possibly because it doesn't exist.=item Can't coerce %s to integer in %s(F) Certain types of SVs, in particular real symbol table entries(typeglobs), can't be forced to stop being what they are.  So you can'tsay things like:    *foo += 1;You CAN say    $foo = *foo;    $foo += 1;but then $foo no longer contains a glob.=item Can't coerce %s to number in %s(F) Certain types of SVs, in particular real symbol table entries(typeglobs), can't be forced to stop being what they are.=item Can't coerce %s to string in %s(F) Certain types of SVs, in particular real symbol table entries(typeglobs), can't be forced to stop being what they are.=item Can't create pipe mailbox(P) An error peculiar to VMS.  The process is suffering from exhausted quotasor other plumbing problems.=item Can't declare %s in my(F) Only scalar, array, and hash variables may be declared as lexical variables.They must have ordinary identifiers as names.=item Can't do inplace edit on %s: %s(S) The creation of the new file failed for the indicated reason.=item Can't do inplace edit without backup(F) You're on a system such as MS-DOS that gets confused if you try readingfrom a deleted (but still opened) file.  You have to say C<-i.bak>, or somesuch.=item Can't do inplace edit: %s E<gt> 14 characters(S) There isn't enough room in the filename to make a backup name for the file.=item Can't do inplace edit: %s is not a regular file(S) You tried to use the B<-i> switch on a special file, such as a file in/dev, or a FIFO.  The file was ignored.=item Can't do setegid!(P) The setegid() call failed for some reason in the setuid emulatorof suidperl.=item Can't do seteuid!(P) The setuid emulator of suidperl failed for some reason.=item Can't do setuid(F) This typically means that ordinary perl tried to exec suidperl todo setuid emulation, but couldn't exec it.  It looks for a name of theform sperl5.000 in the same directory that the perl executable residesunder the name perl5.000, typically /usr/local/bin on Unix machines.If the file is there, check the execute permissions.  If it isn't, askyour sysadmin why he and/or she removed it.=item Can't do waitpid with flags(F) This machine doesn't have either waitpid() or wait4(), so only waitpid()without flags is emulated.=item Can't do {n,m} with n E<gt> m(F) Minima must be less than or equal to maxima.  If you really wantyour regexp to match something 0 times, just put {0}.  See L<perlre>.=item Can't emulate -%s on #! line(F) The #! line specifies a switch that doesn't make sense at this point.For example, it'd be kind of silly to put a B<-x> on the #! line.=item Can't exec "%s": %s(W) An system(), exec(), or piped open call could not execute the namedprogram for the indicated reason.  Typical reasons include: the permissionswere wrong on the file, the file wasn't found in C<$ENV{PATH}>, theexecutable in question was compiled for another architecture, or the#! line in a script points to an interpreter that can't be run forsimilar reasons.  (Or maybe your system doesn't support #! at all.)=item Can't exec %s(F) Perl was trying to execute the indicated program for you because that'swhat the #! line said.  If that's not what you wanted, you may need tomention "perl" on the #! line somewhere.=item Can't execute %s(F) You used the B<-S> switch, but the script to execute could not be foundin the PATH, or at least not with the correct permissions.=item Can't find label %s(F) You said to goto a label that isn't mentioned anywhere that it's possiblefor us to go to.  See L<perlfunc/goto>.=item Can't find string terminator %s anywhere before EOF(F) Perl strings can stretch over multiple lines.  This message means thatthe closing delimiter was omitted.  Because bracketed quotes count nestinglevels, the following is missing its final parenthesis:    print q(The character '(' starts a side comment.)=item Can't fork(F) A fatal error occurred while trying to fork while opening a pipeline.=item Can't get filespec - stale stat buffer?(S) A warning peculiar to VMS.  This arises because of the difference betweenaccess checks under VMS and under the Unix model Perl assumes.  Under VMS,access checks are done by filename, rather than by bits in the stat buffer, sothat ACLs and other protections can be taken into account.  Unfortunately, Perlassumes that the stat buffer contains all the necessary information, and passesit, instead of the filespec, to the access checking routine.  It will try toretrieve the filespec using the device name and FID present in the stat buffer,but this works only if you haven't made a subsequent call to the CRTL stat()routine, because the device name is overwritten with each call.  If this warningappears, the name lookup failed, and the access checking routine gave up andreturned FALSE, just to be conservative.  (Note: The access checking routineknows about the Perl C<stat> operator and file tests, so you shouldn't eversee this warning in response to a Perl command; it arises only if some internalcode takes stat buffers lightly.)=item Can't get pipe mailbox device name(P) An error peculiar to VMS.  After creating a mailbox to act as a pipe, Perlcan't retrieve its name for later use.=item Can't get SYSGEN parameter value for MAXBUF(P) An error peculiar to VMS.  Perl asked $GETSYI how big you want yourmailbox buffers to be, and didn't get an answer.=item Can't goto subroutine outside a subroutine(F) The deeply magical "goto subroutine" call can only replace one subroutinecall for another.  It can't manufacture one out of whole cloth.  In generalyou should be calling it out of only an AUTOLOAD routine anyway.  SeeL<perlfunc/goto>.=item Can't localize a reference(F) You said something like C<local $$ref>, which is not allowed becausethe compiler can't determine whether $ref will end up pointing to anythingwith a symbol table entry, and a symbol table entry is necessary todo a local.=item Can't localize lexical variable %s(F) You used local on a variable name that was previously declared as alexical variable using "my".  This is not allowed.  If you want tolocalize a package variable of the same name, qualify it with thepackage name.=item Can't locate %s in @INC(F) You said to do (or require, or use) a file that couldn't be foundin any of the libraries mentioned in @INC.  Perhaps you need to set thePERL5LIB or PERL5OPT environment variable to say where the extra libraryis, or maybe the script needs to add the library name to @INC.  Or maybeyou just misspelled the name of the file.  See L<perlfunc/require>.=item Can't locate object method "%s" via package "%s"(F) You called a method correctly, and it correctly indicated a packagefunctioning as a class, but that package doesn't define that particularmethod, nor does any of its base classes.  See L<perlobj>.=item Can't locate package %s for @%s::ISA(W) The @ISA array contained the name of another package that doesn't seemto exist.=item Can't mktemp()(F) The mktemp() routine failed for some reason while trying to processa B<-e> switch.  Maybe your /tmp partition is full, or clobbered.=item Can't modify %s in %s(F) You aren't allowed to assign to the item indicated, or otherwise try tochange it, such as with an auto-increment.=item Can't modify nonexistent substring(P) The internal routine that does assignment to a substr() was handeda NULL.=item Can't msgrcv to read-only var(F) The target of a msgrcv must be modifiable to be used as a receivebuffer.=item Can't open %s: %s(S) An inplace edit couldn't open the original file for the indicated reason.Usually this is because you don't have read permission for the file.=item Can't open bidirectional pipe(W) You tried to say C<open(CMD, "|cmd|")>, which is not supported.  You cantry any of several modules in the Perl library to do this, such asIPC::Open2.  Alternately, direct the pipe's output to a file using "E<gt>",and then read it in under a different file handle.=item Can't open error file %s as stderr(F) An error peculiar to VMS.  Perl does its own command line redirection, andcouldn't open the file specified after '2E<gt>' or '2E<gt>E<gt>' on thecommand line for writing.=item Can't open input file %s as stdin(F) An error peculiar to VMS.  Perl does its own command line redirection, andcouldn't open the file specified after 'E<lt>' on the command line for reading.=item Can't open output file %s as stdout(F) An error peculiar to VMS.  Perl does its own command line redirection, andcouldn't open the file specified after 'E<gt>' or 'E<gt>E<gt>' on the commandline for writing.=item Can't open output pipe (name: %s)(P) An error peculiar to VMS.  Perl does its own command line redirection, andcouldn't open the pipe into which to send data destined for stdout.=item Can't open perl script "%s": %s(F) The script you specified can't be opened for the indicated reason.=item Can't redefine active sort subroutine %s(F) Perl optimizes the internal handling of sort subroutines and keepspointers into them.  You tried to redefine one such sort subroutine when itwas currently active, which is not allowed.  If you really want to dothis, you should write C<sort { &func } @x> instead of C<sort func @x>.=item Can't rename %s to %s: %s, skipping file(S) The rename done by the B<-i> switch failed for some reason, probably becauseyou don't have write permission to the directory.=item Can't reopen input pipe (name: %s) in binary mode(P) An error peculiar to VMS.  Perl thought stdin was a pipe, and tried toreopen it to accept binary data.  Alas, it failed.=item Can't reswap uid and euid(P) The setreuid() call failed for some reason in the setuid emulatorof suidperl.=item Can't return outside a subroutine(F) The return statement was executed in mainline code, that is, wherethere was no subroutine call to return out of.  See L<perlsub>.=item Can't stat script "%s"(P) For some reason you can't fstat() the script even though you haveit open already.  Bizarre.=item Can't swap uid and euid(P) The setreuid() call failed for some reason in the setuid emulatorof suidperl.=item Can't take log of %g(F) Logarithms are defined on only positive real numbers.=item Can't take sqrt of %g(F) For ordinary real numbers, you can't take the square root of anegative number.  There's a Complex package available for Perl, though,if you really want to do that.=item Can't undef active subroutine(F) You can't undefine a routine that's currently running.  You can,however, redefine it while it's running, and you can even undef theredefined subroutine while the old routine is running.  Go figure.=item Can't unshift(F) You tried to unshift an "unreal" array that can't be unshifted, suchas the main Perl stack.=item Can't upgrade that kind of scalar(P) The internal sv_upgrade routine adds "members" to an SV, makingit into a more specialized kind of SV.  The top several SV types areso specialized, however, that they cannot be interconverted.  Thismessage indicates that such a conversion was attempted.=item Can't upgrade to undef(P) The undefined SV is the bottom of the totem pole, in the schemeof upgradability.  Upgrading to undef indicates an error in thecode calling sv_upgrade.=item Can't use "my %s" in sort comparison(F) The global variables $a and $b are reserved for sort comparisons.You mentioned $a or $b in the same line as the E<lt>=E<gt> or cmp operator,and the variable had earlier been declared as a lexical variable.Either qualify the sort variable with the package name, or rename thelexical variable.=item Can't use %s for loop variable(F) Only a simple scalar variable may be used as a loop variable on a foreach.=item Can't use %s ref as %s ref(F) You've mixed up your reference types.  You have to dereference areference of the type needed.  You can use the ref() function totest the type of the reference, if need be.=item Can't use \1 to mean $1 in expression(W) In an ordinary expression, backslash is a unary operator that createsa reference to its argument.  The use of backslash to indicate a backreferenceto a matched substring is valid only as part of a regular expression pattern.Trying to do this in ordinary Perl code produces a value that printsout looking like SCALAR(0xdecaf).  Use the $1 form instead.=item Can't use bareword ("%s") as %s ref while \"strict refs\" in use(F) Only hard references are allowed by "strict refs".  Symbolic referencesare disallowed.  See L<perlref>.=item Can't use string ("%s") as %s ref while "strict refs" in use(F) Only hard references are allowed by "strict refs".  Symbolic referencesare disallowed.  See L<perlref>.=item Can't use an undefined value as %s reference(F) A value used as either a hard reference or a symbolic reference mustbe a defined value.  This helps to delurk some insidious errors.=item Can't use global %s in "my"(F) You tried to declare a magical variable as a lexical variable.  This isnot allowed, because the magic can be tied to only one location (namelythe global variable) and it would be incredibly confusing to havevariables in your program that looked like magical variables butweren't.=item Can't use subscript on %s(F) The compiler tried to interpret a bracketed expression as asubscript.  But to the left of the brackets was an expression thatdidn't look like an array reference, or anything else subscriptable.=item Can't write to temp file for B<-e>: %s(F) The write routine failed for some reason while trying to processa B<-e> switch.  Maybe your /tmp partition is full, or clobbered.=item Can't x= to read-only value(F) You tried to repeat a constant value (often the undefined value) withan assignment operator, which implies modifying the value itself.Perhaps you need to copy the value to a temporary, and repeat that.=item Cannot open temporary file(F) The create routine failed for some reason while trying to processa B<-e> switch.  Maybe your /tmp partition is full, or clobbered.=item Cannot resolve method `%s' overloading `%s' in package `%s'(F|P) Error resolving overloading specified by a method name (asopposed to a subroutine reference): no such method callable via thepackage. If method name is C<???>, this is an internal error.=item chmod: mode argument is missing initial 0(W) A novice will sometimes say    chmod 777, $filenamenot realizing that 777 will be interpreted as a decimal number, equivalentto 01411.  Octal constants are introduced with a leading 0 in Perl, as in C.=item Close on unopened file E<lt>%sE<gt>(W) You tried to close a filehandle that was never opened.=item Compilation failed in require(F) Perl could not compile a file specified in a C<require> statement.Perl uses this generic message when none of the errors that it encounteredwere severe enough to halt compilation immediately.=item connect() on closed fd(W) You tried to do a connect on a closed socket.  Did you forget to checkthe return value of your socket() call?  See L<perlfunc/connect>.=item Constant subroutine %s redefined(S) You redefined a subroutine which had previously been eligible forinlining.  See L<perlsub/"Constant Functions"> for commentary andworkarounds.=item Constant subroutine %s undefined(S) You undefined a subroutine which had previously been eligible forinlining.  See L<perlsub/"Constant Functions"> for commentary andworkarounds.=item Copy method did not return a reference(F) The method which overloads "=" is buggy. See L<overload/Copy Constructor>.=item Corrupt malloc ptr 0x%lx at 0x%lx(P) The malloc package that comes with Perl had an internal failure.=item corrupted regexp pointers(P) The regular expression engine got confused by what the regularexpression compiler gave it.=item corrupted regexp program(P) The regular expression engine got passed a regexp program withouta valid magic number.=item Deep recursion on subroutine "%s"(W) This subroutine has called itself (directly or indirectly) 100times than it has returned.  This probably indicates an infiniterecursion, unless you're writing strange benchmark programs, in whichcase it indicates something else.=item Delimiter for here document is too long(F) In a here document construct like C<E<lt>E<lt>FOO>, the labelC<FOO> is too long for Perl to handle.  You have to be seriouslytwisted to write code that triggers this error.=item Did you mean &%s instead?(W) You probably referred to an imported subroutine &FOO as $FOO or some such.=item Did you mean $ or @ instead of %?(W) You probably said %hash{$key} when you meant $hash{$key} or @hash{@keys}.On the other hand, maybe you just meant %hash and got carried away.=item Died(F) You passed die() an empty string (the equivalent of C<die "">) oryou called it with no args and both C<$@> and C<$_> were empty.=item Do you need to predeclare %s?(S) This is an educated guess made in conjunction with the message "%sfound where operator expected".  It often means a subroutine or modulename is being referenced that hasn't been declared yet.  This may bebecause of ordering problems in your file, or because of a missing"sub", "package", "require", or "use" statement.  If you'rereferencing something that isn't defined yet, you don't actually haveto define the subroutine or package before the current location.  Youcan use an empty "sub foo;" or "package FOO;" to enter a "forward"declaration.=item Don't know how to handle magic of type '%s'(P) The internal handling of magical variables has been cursed.=item do_study: out of memory(P) This should have been caught by safemalloc() instead.=item Duplicate free() ignored(S) An internal routine called free() on something that had alreadybeen freed.=item elseif should be elsif(S) There is no keyword "elseif" in Perl because Larry thinks it'sugly.  Your code will be interpreted as an attempt to call a methodnamed "elseif" for the class returned by the following block.  This isunlikely to be what you want.=item END failed--cleanup aborted(F) An untrapped exception was raised while executing an END subroutine.The interpreter is immediately exited.=item Error converting file specification %s(F) An error peculiar to VMS.  Because Perl may have to deal with filespecifications in either VMS or Unix syntax, it converts them to asingle form when it must operate on them directly.  Either you'vepassed an invalid file specification to Perl, or you've found acase the conversion routines don't handle.  Drat.=item Excessively long <> operator(F) The contents of a <> operator may not exceed the maximum size of aPerl identifier.  If you're just trying to glob a long list offilenames, try using the glob() operator, or put the filenames into avariable and glob that.=item Execution of %s aborted due to compilation errors(F) The final summary message when a Perl compilation fails.=item Exiting eval via %s(W) You are exiting an eval by unconventional means, such asa goto, or a loop control statement.=item Exiting pseudo-block via %s(W) You are exiting a rather special block construct (like a sort block orsubroutine) by unconventional means, such as a goto, or a loop controlstatement.  See L<perlfunc/sort>.=item Exiting subroutine via %s(W) You are exiting a subroutine by unconventional means, such asa goto, or a loop control statement.=item Exiting substitution via %s(W) You are exiting a substitution by unconventional means, such asa return, a goto, or a loop control statement.=item Fatal VMS error at %s, line %d(P) An error peculiar to VMS.  Something untoward happened in a VMS systemservice or RTL routine; Perl's exit status should provide more details.  Thefilename in "at %s" and the line number in "line %d" tell you which section ofthe Perl source code is distressed.=item fcntl is not implemented(F) Your machine apparently doesn't implement fcntl().  What is this, aPDP-11 or something?=item Filehandle %s never opened(W) An I/O operation was attempted on a filehandle that was never initialized.You need to do an open() or a socket() call, or call a constructor fromthe FileHandle package.=item Filehandle %s opened for only input(W) You tried to write on a read-only filehandle.  If youintended it to be a read-write filehandle, you needed to open it with"+E<lt>" or "+E<gt>" or "+E<gt>E<gt>" instead of with "E<lt>" or nothing.  Ifyou intended only to write the file, use "E<gt>" or "E<gt>E<gt>".  SeeL<perlfunc/open>.=item Filehandle opened for only input(W) You tried to write on a read-only filehandle.  If youintended it to be a read-write filehandle, you needed to open it with"+E<lt>" or "+E<gt>" or "+E<gt>E<gt>" instead of with "E<lt>" or nothing.  Ifyou intended only to write the file, use "E<gt>" or "E<gt>E<gt>".  SeeL<perlfunc/open>.=item Final $ should be \$ or $name(F) You must now decide whether the final $ in a string was meant to bea literal dollar sign, or was meant to introduce a variable namethat happens to be missing.  So you have to put either the backslash orthe name.=item Final @ should be \@ or @name(F) You must now decide whether the final @ in a string was meant to bea literal "at" sign, or was meant to introduce a variable namethat happens to be missing.  So you have to put either the backslash orthe name.=item Format %s redefined(W) You redefined a format.  To suppress this warning, say    {	local $^W = 0;	eval "format NAME =...";    }=item Format not terminated(F) A format must be terminated by a line with a solitary dot.  Perl gotto the end of your file without finding such a line.=item Found = in conditional, should be ==(W) You said    if ($foo = 123)when you meant    if ($foo == 123)(or something like that).=item gdbm store returned %d, errno %d, key "%s"(S) A warning from the GDBM_File extension that a store failed.=item gethostent not implemented(F) Your C library apparently doesn't implement gethostent(), probablybecause if it did, it'd feel morally obligated to return every hostnameon the Internet.=item get{sock,peer}name() on closed fd(W) You tried to get a socket or peer socket name on a closed socket.Did you forget to check the return value of your socket() call?=item getpwnam returned invalid UIC %#o for user "%s"(S) A warning peculiar to VMS.  The call to C<sys$getuai> underlying theC<getpwnam> operator returned an invalid UIC.=item Glob not terminated(F) The lexer saw a left angle bracket in a place where it was expectinga term, so it's looking for the corresponding right angle bracket, and notfinding it.  Chances are you left some needed parentheses out earlier inthe line, and you really meant a "less than".=item Global symbol "%s" requires explicit package name(F) You've said "use strict vars", which indicates that all variablesmust either be lexically scoped (using "my"), or explicitly qualified tosay which package the global variable is in (using "::").=item goto must have label(F) Unlike with "next" or "last", you're not allowed to goto anunspecified destination.  See L<perlfunc/goto>.=item Had to create %s unexpectedly(S) A routine asked for a symbol from a symbol table that ought to haveexisted already, but for some reason it didn't, and had to be created onan emergency basis to prevent a core dump.=item Hash %%s missing the % in argument %d of %s()(D) Really old Perl let you omit the % on hash names in some spots.  Thisis now heavily deprecated.=item Identifier too long(F) Perl limits identifiers (names for variables, functions, etc.) toabout 250 characters for simple names, and somewhat more for compoundnames (like C<$A::B>).  You've exceeded Perl's limits.  Futureversions of Perl are likely to eliminate these arbitrary limitations.=item Ill-formed logical name |%s| in prime_env_iter(W) A warning peculiar to VMS.  A logical name was encountered when preparingto iterate over %ENV which violates the syntactic rules governing logicalnames.  Because it cannot be translated normally, it is skipped, and will notappear in %ENV.  This may be a benign occurrence, as some software packagesmight directly modify logical name tables and introduce nonstandard names,or it may indicate that a logical name table has been corrupted.=item Illegal character %s (carriage return)(F) A carriage return character was found in the input.  This is anerror, and not a warning, because carriage return characters can breakmulti-line strings, including here documents (e.g., C<print E<lt>E<lt>EOF;>).Under Unix, this error is usually caused by executing Perl code --either the main program, a module, or an eval'd string -- that wastransferred over a network connection from a non-Unix system withoutproperly converting the text file format.Under systems that use something other than '\n' to delimit lines oftext, this error can also be caused by reading Perl code from a filehandle that is in binary mode (as set by the C<binmode> operator).In either case, the Perl code in question will probably need to beconverted with something like C<s/\x0D\x0A?/\n/g> before it can beexecuted.=item Illegal division by zero(F) You tried to divide a number by 0.  Either something was wrong in yourlogic, or you need to put a conditional in to guard against meaningless input.=item Illegal modulus zero(F) You tried to divide a number by 0 to get the remainder.  Most numbersdon't take to this kindly.=item Illegal octal digit(F) You used an 8 or 9 in a octal number.=item Illegal octal digit ignored(W) You may have tried to use an 8 or 9 in a octal number.  Interpretationof the octal number stopped before the 8 or 9.=item Illegal switch in PERL5OPT: %s(X) The PERL5OPT environment variable may only be used to set thefollowing switches: B<-[DIMUdmw]>.=item In string, @%s now must be written as \@%s(F) It used to be that Perl would try to guess whether you wanted anarray interpolated or a literal @.  It did this when the string was firstused at runtime.  Now strings are parsed at compile time, and ambiguousinstances of @ must be disambiguated, either by prepending a backslash toindicate a literal, or by declaring (or using) the array within theprogram before the string (lexically).  (Someday it will simply assumethat an unbackslashed @ interpolates an array.)=item Insecure dependency in %s(F) You tried to do something that the tainting mechanism didn't like.The tainting mechanism is turned on when you're running setuid or setgid,or when you specify B<-T> to turn it on explicitly.  The tainting mechanismlabels all data that's derived directly or indirectly from the user,who is considered to be unworthy of your trust.  If any such data isused in a "dangerous" operation, you get this error.  See L<perlsec>for more information.=item Insecure directory in %s(F) You can't use system(), exec(), or a piped open in a setuid or setgidscript if C<$ENV{PATH}> contains a directory that is writable by the world.See L<perlsec>.=item Insecure PATH(F) You can't use system(), exec(), or a piped open in a setuid orsetgid script if C<$ENV{PATH}> is derived from data supplied (orpotentially supplied) by the user.  The script must set the path to aknown value, using trustworthy data.  See L<perlsec>.=item Integer overflow in hex number(S) The literal hex number you have specified is too big for yourarchitecture. On a 32-bit architecture the largest hex literal is0xFFFFFFFF.=item Integer overflow in octal number(S) The literal octal number you have specified is too big for yourarchitecture. On a 32-bit architecture the largest octal literal is037777777777.=item Internal inconsistency in tracking vforks(S) A warning peculiar to VMS.  Perl keeps track of the numberof times you've called C<fork> and C<exec>, to determinewhether the current call to C<exec> should affect the currentscript or a subprocess (see L<perlvms/exec>).  Somehow, this counthas become scrambled, so Perl is making a guess and treatingthis C<exec> as a request to terminate the Perl scriptand execute the specified command.=item internal disaster in regexp(P) Something went badly wrong in the regular expression parser.=item internal error: glob failed(P) Something went wrong with the external program(s) used for C<glob>and C<E<lt>*.cE<gt>>.  This may mean that your csh (C shell) isbroken.  If so, you should change all of the csh-related variables inconfig.sh:  If you have tcsh, make the variables refer to it as if itwere csh (e.g. C<full_csh='/usr/bin/tcsh'>); otherwise, make them allempty (except that C<d_csh> should be C<'undef'>) so that Perl willthink csh is missing.  In either case, after editing config.sh, runC<./Configure -S> and rebuild Perl.=item internal urp in regexp at /%s/(P) Something went badly awry in the regular expression parser.=item invalid [] range in regexp(F) The range specified in a character class had a minimum charactergreater than the maximum character.  See L<perlre>.=item Invalid conversion in %s: "%s"(W) Perl does not understand the given format conversion.See L<perlfunc/sprintf>.=item Invalid type in pack: '%s'(F) The given character is not a valid pack type.  See L<perlfunc/pack>.=item Invalid type in unpack: '%s'(F) The given character is not a valid unpack type.  See L<perlfunc/unpack>.=item ioctl is not implemented(F) Your machine apparently doesn't implement ioctl(), which is prettystrange for a machine that supports C.=item junk on end of regexp(P) The regular expression parser is confused.=item Label not found for "last %s"(F) You named a loop to break out of, but you're not currently in aloop of that name, not even if you count where you were called from.See L<perlfunc/last>.=item Label not found for "next %s"(F) You named a loop to continue, but you're not currently in a loop ofthat name, not even if you count where you were called from.  SeeL<perlfunc/last>.=item Label not found for "redo %s"(F) You named a loop to restart, but you're not currently in a loop ofthat name, not even if you count where you were called from.  SeeL<perlfunc/last>.=item listen() on closed fd(W) You tried to do a listen on a closed socket.  Did you forget to checkthe return value of your socket() call?  See L<perlfunc/listen>.=item Method for operation %s not found in package %s during blessing(F) An attempt was made to specify an entry in an overloading table thatdoesn't resolve to a valid subroutine.  See L<overload>.=item Might be a runaway multi-line %s string starting on line %d(S) An advisory indicating that the previous error may have been causedby a missing delimiter on a string or pattern, because it eventuallyended earlier on the current line.=item Misplaced _ in number(W) An underline in a decimal constant wasn't on a 3-digit boundary.=item Missing $ on loop variable(F) Apparently you've been programming in B<csh> too much.  Variables are alwaysmentioned with the $ in Perl, unlike in the shells, where it can vary fromone line to the next.=item Missing comma after first argument to %s function(F) While certain functions allow you to specify a filehandle or an"indirect object" before the argument list, this ain't one of them.=item Missing operator before %s?(S) This is an educated guess made in conjunction with the message "%sfound where operator expected".  Often the missing operator is a comma.=item Missing right bracket(F) The lexer counted more opening curly brackets (braces) than closing ones.As a general rule, you'll find it's missing near the place you were lastediting.=item Missing semicolon on previous line?(S) This is an educated guess made in conjunction with the message "%sfound where operator expected".  Don't automatically put a semicolon onthe previous line just because you saw this message.=item Modification of a read-only value attempted(F) You tried, directly or indirectly, to change the value of aconstant.  You didn't, of course, try "2 = 1", because the compilercatches that.  But an easy way to do the same thing is:    sub mod { $_[0] = 1 }    mod(2);Another way is to assign to a substr() that's off the end of the string.=item Modification of noncreatable array value attempted, subscript %d(F) You tried to make an array value spring into existence, and thesubscript was probably negative, even counting from end of the arraybackwards.=item Modification of noncreatable hash value attempted, subscript "%s"(F) You tried to make a hash value spring into existence, and it couldn'tbe created for some peculiar reason.=item Module name must be constant(F) Only a bare module name is allowed as the first argument to a "use".=item msg%s not implemented(F) You don't have System V message IPC on your system.=item Multidimensional syntax %s not supported(W) Multidimensional arrays aren't written like C<$foo[1,2,3]>.  They're writtenlike C<$foo[1][2][3]>, as in C.=item Name "%s::%s" used only once: possible typo(W) Typographical errors often show up as unique variable names.If you had a good reason for having a unique name, then just mentionit again somehow to suppress the message.  The C<use vars> pragma isprovided for just this purpose.=item Negative length(F) You tried to do a read/write/send/recv operation with a buffer lengththat is less than 0.  This is difficult to imagine.=item nested *?+ in regexp(F) You can't quantify a quantifier without intervening parentheses.  Sothings like ** or +* or ?* are illegal.Note, however, that the minimal matching quantifiers, C<*?>, C<+?>, and C<??> appearto be nested quantifiers, but aren't.  See L<perlre>.=item No #! line(F) The setuid emulator requires that scripts have a well-formed #! lineeven on machines that don't support the #! construct.=item No %s allowed while running setuid(F) Certain operations are deemed to be too insecure for a setuid or setgidscript to even be allowed to attempt.  Generally speaking there will beanother way to do what you want that is, if not secure, at least securable.See L<perlsec>.=item No B<-e> allowed in setuid scripts(F) A setuid script can't be specified by the user.=item No comma allowed after %s(F) A list operator that has a filehandle or "indirect object" is notallowed to have a comma between that and the following arguments.Otherwise it'd be just another one of the arguments.One possible cause for this is that you expected to have imported aconstant to your name space with B<use> or B<import> while no suchimporting took place, it may for example be that your operating systemdoes not support that particular constant. Hopefully you did use anexplicit import list for the constants you expect to see, please seeL<perlfunc/use> and L<perlfunc/import>. While an explicit import listwould probably have caught this error earlier it naturally does notremedy the fact that your operating system still does not support thatconstant. Maybe you have a typo in the constants of the symbol importlist of B<use> or B<import> or in the constant name at the line wherethis error was triggered?=item No command into which to pipe on command line(F) An error peculiar to VMS.  Perl handles its own command line redirection,and found a '|' at the end of the command line, so it doesn't know where youwant to pipe the output from this command.=item No DB::DB routine defined(F) The currently executing code was compiled with the B<-d> switch,but for some reason the perl5db.pl file (or some facsimile thereof)didn't define a routine to be called at the beginning of eachstatement.  Which is odd, because the file should have been requiredautomatically, and should have blown up the require if it didn't parseright.=item No dbm on this machine(P) This is counted as an internal error, because every machine shouldsupply dbm nowadays, because Perl comes with SDBM.  See L<SDBM_File>.=item No DBsub routine(F) The currently executing code was compiled with the B<-d> switch,but for some reason the perl5db.pl file (or some facsimile thereof)didn't define a DB::sub routine to be called at the beginning of eachordinary subroutine call.=item No error file after 2E<gt> or 2E<gt>E<gt> on command line(F) An error peculiar to VMS.  Perl handles its own command line redirection,and found a '2E<gt>' or a '2E<gt>E<gt>' on the command line, but can't findthe name of the file to which to write data destined for stderr.=item No input file after E<lt> on command line(F) An error peculiar to VMS.  Perl handles its own command line redirection,and found a 'E<lt>' on the command line, but can't find the name of the filefrom which to read data for stdin.=item No output file after E<gt> on command line(F) An error peculiar to VMS.  Perl handles its own command line redirection,and found a lone 'E<gt>' at the end of the command line, so it doesn't knowwhere you wanted to redirect stdout.=item No output file after E<gt> or E<gt>E<gt> on command line(F) An error peculiar to VMS.  Perl handles its own command line redirection,and found a 'E<gt>' or a 'E<gt>E<gt>' on the command line, but can't find thename of the file to which to write data destined for stdout.=item No Perl script found in input(F) You called C<perl -x>, but no line was found in the file beginningwith #! and containing the word "perl".=item No setregid available(F) Configure didn't find anything resembling the setregid() call foryour system.=item No setreuid available(F) Configure didn't find anything resembling the setreuid() call foryour system.=item No space allowed after B<-I>(F) The argument to B<-I> must follow the B<-I> immediately with nointervening space.=item No such pipe open(P) An error peculiar to VMS.  The internal routine my_pclose() tried toclose a pipe which hadn't been opened.  This should have been caught earlier asan attempt to close an unopened filehandle.=item No such signal: SIG%s(W) You specified a signal name as a subscript to %SIG that was not recognized.Say C<kill -l> in your shell to see the valid signal names on your system.=item Not a CODE reference(F) Perl was trying to evaluate a reference to a code value (that is, asubroutine), but found a reference to something else instead.  You canuse the ref() function to find out what kind of ref it really was.See also L<perlref>.=item Not a format reference(F) I'm not sure how you managed to generate a reference to an anonymousformat, but this indicates you did, and that it didn't exist.=item Not a GLOB reference(F) Perl was trying to evaluate a reference to a "typeglob" (that is,a symbol table entry that looks like C<*foo>), but found a reference tosomething else instead.  You can use the ref() function to find outwhat kind of ref it really was.  See L<perlref>.=item Not a HASH reference(F) Perl was trying to evaluate a reference to a hash value, butfound a reference to something else instead.  You can use the ref()function to find out what kind of ref it really was.  See L<perlref>.=item Not a perl script(F) The setuid emulator requires that scripts have a well-formed #! lineeven on machines that don't support the #! construct.  The line mustmention perl.=item Not a SCALAR reference(F) Perl was trying to evaluate a reference to a scalar value, butfound a reference to something else instead.  You can use the ref()function to find out what kind of ref it really was.  See L<perlref>.=item Not a subroutine reference(F) Perl was trying to evaluate a reference to a code value (that is, asubroutine), but found a reference to something else instead.  You canuse the ref() function to find out what kind of ref it really was.See also L<perlref>.=item Not a subroutine reference in overload table(F) An attempt was made to specify an entry in an overloading table thatdoesn't somehow point to a valid subroutine.  See L<overload>.=item Not an ARRAY reference(F) Perl was trying to evaluate a reference to an array value, butfound a reference to something else instead.  You can use the ref()function to find out what kind of ref it really was.  See L<perlref>.=item Not enough arguments for %s(F) The function requires more arguments than you specified.=item Not enough format arguments(W) A format specified more picture fields than the next line supplied.See L<perlform>.=item Null filename used(F) You can't require the null filename, especially because on many machinesthat means the current directory!  See L<perlfunc/require>.=item Null picture in formline(F) The first argument to formline must be a valid format picturespecification.  It was found to be empty, which probably means yousupplied it an uninitialized value.  See L<perlform>.=item NULL OP IN RUN(P) Some internal routine called run() with a null opcode pointer.=item Null realloc(P) An attempt was made to realloc NULL.=item NULL regexp argument(P) The internal pattern matching routines blew it big time.=item NULL regexp parameter(P) The internal pattern matching routines are out of their gourd.=item Number too long(F) Perl limits the representation of decimal numbers in programs to aboutabout 250 characters.  You've exceeded that length.  Future versions ofPerl are likely to eliminate this arbitrary limitation.  In the meantime,try using scientific notation (e.g. "1e6" instead of "1_000_000").=item Odd number of elements in hash list(S) You specified an odd number of elements to a hash list, which is odd,because hash lists come in key/value pairs.=item Offset outside string(F) You tried to do a read/write/send/recv operation with an offsetpointing outside the buffer.  This is difficult to imagine.The sole exception to this is that C<sysread()>ing past the bufferwill extend the buffer and zero pad the new area.=item oops: oopsAV(S) An internal warning that the grammar is screwed up.=item oops: oopsHV(S) An internal warning that the grammar is screwed up.=item Operation `%s': no method found,%s(F) An attempt was made to perform an overloaded operation for whichno handler was defined.  While some handlers can be autogenerated interms of other handlers, there is no default handler for anyoperation, unless C<fallback> overloading key is specified to betrue.  See L<overload>.=item Operator or semicolon missing before %s(S) You used a variable or subroutine call where the parser wasexpecting an operator.  The parser has assumed you really meantto use an operator, but this is highly likely to be incorrect.For example, if you say "*foo *foo" it will be interpreted asif you said "*foo * 'foo'".=item Out of memory for yacc stack(F) The yacc parser wanted to grow its stack so it could continue parsing,but realloc() wouldn't give it more memory, virtual or otherwise.=item Out of memory!(X|F) The malloc() function returned 0, indicating there was insufficientremaining memory (or virtual memory) to satisfy the request.The request was judged to be small, so the possibility to trap itdepends on the way perl was compiled.  By default it is not trappable.However, if compiled for this, Perl may use the contents of C<$^M> asan emergency pool after die()ing with this message.  In this case theerror is trappable I<once>.=item Out of memory during request for %s(F) The malloc() function returned 0, indicating there was insufficientremaining memory (or virtual memory) to satisfy the request. However,the request was judged large enough (compile-time default is 64K), soa possibility to shut down by trapping this error is granted.=item page overflow(W) A single call to write() produced more lines than can fit on a page.See L<perlform>.=item panic: ck_grep(P) Failed an internal consistency check trying to compile a grep.=item panic: ck_split(P) Failed an internal consistency check trying to compile a split.=item panic: corrupt saved stack index(P) The savestack was requested to restore more localized values than thereare in the savestack.=item panic: die %s(P) We popped the context stack to an eval context, and then discoveredit wasn't an eval context.=item panic: do_match(P) The internal pp_match() routine was called with invalid operational data.=item panic: do_split(P) Something terrible went wrong in setting up for the split.=item panic: do_subst(P) The internal pp_subst() routine was called with invalid operational data.=item panic: do_trans(P) The internal do_trans() routine was called with invalid operational data.=item panic: frexp(P) The library function frexp() failed, making printf("%f") impossible.=item panic: goto(P) We popped the context stack to a context with the specified label,and then discovered it wasn't a context we know how to do a goto in.=item panic: INTERPCASEMOD(P) The lexer got into a bad state at a case modifier.=item panic: INTERPCONCAT(P) The lexer got into a bad state parsing a string with brackets.=item panic: last(P) We popped the context stack to a block context, and then discoveredit wasn't a block context.=item panic: leave_scope clearsv(P) A writable lexical variable became read-only somehow within the scope.=item panic: leave_scope inconsistency(P) The savestack probably got out of sync.  At least, there was aninvalid enum on the top of it.=item panic: malloc(P) Something requested a negative number of bytes of malloc.=item panic: mapstart(P) The compiler is screwed up with respect to the map() function.=item panic: null array(P) One of the internal array routines was passed a null AV pointer.=item panic: pad_alloc(P) The compiler got confused about which scratch pad it was allocatingand freeing temporaries and lexicals from.=item panic: pad_free curpad(P) The compiler got confused about which scratch pad it was allocatingand freeing temporaries and lexicals from.=item panic: pad_free po(P) An invalid scratch pad offset was detected internally.=item panic: pad_reset curpad(P) The compiler got confused about which scratch pad it was allocatingand freeing temporaries and lexicals from.=item panic: pad_sv po(P) An invalid scratch pad offset was detected internally.=item panic: pad_swipe curpad(P) The compiler got confused about which scratch pad it was allocatingand freeing temporaries and lexicals from.=item panic: pad_swipe po(P) An invalid scratch pad offset was detected internally.=item panic: pp_iter(P) The foreach iterator got called in a non-loop context frame.=item panic: realloc(P) Something requested a negative number of bytes of realloc.=item panic: restartop(P) Some internal routine requested a goto (or something like it), anddidn't supply the destination.=item panic: return(P) We popped the context stack to a subroutine or eval context, andthen discovered it wasn't a subroutine or eval context.=item panic: scan_num(P) scan_num() got called on something that wasn't a number.=item panic: sv_insert(P) The sv_insert() routine was told to remove more string than therewas string.=item panic: top_env(P) The compiler attempted to do a goto, or something weird like that.=item panic: yylex(P) The lexer got into a bad state while processing a case modifier.=item Pareneses missing around "%s" list(W) You said something like    my $foo, $bar = @_;when you meant    my ($foo, $bar) = @_;Remember that "my" and "local" bind closer than comma.=item Perl %3.3f required--this is only version %s, stopped(F) The module in question uses features of a version of Perl more recentthan the currently running version.  How long has it been since you upgraded,anyway?  See L<perlfunc/require>.=item Permission denied(F) The setuid emulator in suidperl decided you were up to no good.=item pid %d not a child(W) A warning peculiar to VMS.  Waitpid() was asked to wait for a process whichisn't a subprocess of the current process.  While this is fine from VMS'perspective, it's probably not what you intended.=item POSIX getpgrp can't take an argument(F) Your C compiler uses POSIX getpgrp(), which takes no argument, unlikethe BSD version, which takes a pid.=item Possible attempt to put comments in qw() list(W) qw() lists contain items separated by whitespace; as with literalstrings, comment characters are not ignored, but are instead treatedas literal data.  (You may have used different delimiters than theexclamation marks parentheses shown here; braces are also frequentlyused.)You probably wrote something like this:    @list = qw(	a # a comment        b # another comment    );when you should have written this:    @list = qw(	a        b    );If you really want comments, build your list theold-fashioned way, with quotes and commas:    @list = (        'a',    # a comment        'b',    # another comment    );=item Possible attempt to separate words with commas(W) qw() lists contain items separated by whitespace; therefore commasaren't needed to separate the items.  (You may have used differentdelimiters than the parentheses shown here; braces are also frequentlyused.)You probably wrote something like this:    qw! a, b, c !;which puts literal commas into some of the list items.  Write it withoutcommas if you don't want them to appear in your data:    qw! a b c !;=item Possible memory corruption: %s overflowed 3rd argument(F) An ioctl() or fcntl() returned more than Perl was bargaining for.Perl guesses a reasonable buffer size, but puts a sentinel byte at theend of the buffer just in case.  This sentinel byte got clobbered, andPerl assumes that memory is now corrupted.  See L<perlfunc/ioctl>.=item Precedence problem: open %s should be open(%s)(S) The old irregular construct    open FOO || die;is now misinterpreted as    open(FOO || die);because of the strict regularization of Perl 5's grammar into unaryand list operators.  (The old open was a little of both.)  You mustput parentheses around the filehandle, or use the new "or" operatorinstead of "||".=item print on closed filehandle %s(W) The filehandle you're printing on got itself closed sometime before now.Check your logic flow.=item printf on closed filehandle %s(W) The filehandle you're writing to got itself closed sometime before now.Check your logic flow.=item Probable precedence problem on %s(W) The compiler found a bareword where it expected a conditional,which often indicates that an || or && was parsed as part of thelast argument of the previous construct, for example:    open FOO || die;=item Prototype mismatch: %s vs %s(S) The subroutine being declared or defined had previously been declaredor defined with a different function prototype.=item Read on closed filehandle E<lt>%sE<gt>(W) The filehandle you're reading from got itself closed sometime before now.Check your logic flow.=item Reallocation too large: %lx(F) You can't allocate more than 64K on an MS-DOS machine.=item Recompile perl with B<-D>DEBUGGING to use B<-D> switch(F) You can't use the B<-D> option unless the code to produce thedesired output is compiled into Perl, which entails some overhead,which is why it's currently left out of your copy.=item Recursive inheritance detected(F) More than 100 levels of inheritance were used.  Probably indicatesan unintended loop in your inheritance hierarchy.=item Reference miscount in sv_replace()(W) The internal sv_replace() function was handed a new SV with areference count of other than 1.=item regexp memory corruption(P) The regular expression engine got confused by what the regularexpression compiler gave it.=item regexp out of space(P) A "can't happen" error, because safemalloc() should have caught it earlier.=item regexp too big(F) The current implementation of regular expressions uses shorts asaddress offsets within a string.  Unfortunately this means that ifthe regular expression compiles to longer than 32767, it'll blow up.Usually when you want a regular expression this big, there is a betterway to do it with multiple statements.  See L<perlre>.=item Reversed %s= operator(W) You wrote your assignment operator backwards.  The = must alwayscomes last, to avoid ambiguity with subsequent unary operators.=item Runaway format(F) Your format contained the ~~ repeat-until-blank sequence, but itproduced 200 lines at once, and the 200th line looked exactly like the199th line.  Apparently you didn't arrange for the arguments to exhaustthemselves, either by using ^ instead of @ (for scalar variables), or byshifting or popping (for array variables).  See L<perlform>.=item Scalar value @%s[%s] better written as $%s[%s](W) You've used an array slice (indicated by @) to select a single element ofan array.  Generally it's better to ask for a scalar value (indicated by $).The difference is that C<$foo[&bar]> always behaves like a scalar, both whenassigning to it and when evaluating its argument, while C<@foo[&bar]> behaveslike a list when you assign to it, and provides a list context to itssubscript, which can do weird things if you're expecting only one subscript.On the other hand, if you were actually hoping to treat the arrayelement as a list, you need to look into how references work, becausePerl will not magically convert between scalars and lists for you.  SeeL<perlref>.=item Scalar value @%s{%s} better written as $%s{%s}(W) You've used a hash slice (indicated by @) to select a single element ofa hash.  Generally it's better to ask for a scalar value (indicated by $).The difference is that C<$foo{&bar}> always behaves like a scalar, both whenassigning to it and when evaluating its argument, while C<@foo{&bar}> behaveslike a list when you assign to it, and provides a list context to itssubscript, which can do weird things if you're expecting only one subscript.On the other hand, if you were actually hoping to treat the hashelement as a list, you need to look into how references work, becausePerl will not magically convert between scalars and lists for you.  SeeL<perlref>.=item Script is not setuid/setgid in suidperl(F) Oddly, the suidperl program was invoked on a script without a setuidor setgid bit set.  This doesn't make much sense.=item Search pattern not terminated(F) The lexer couldn't find the final delimiter of a // or m{}construct.  Remember that bracketing delimiters count nesting level.=item %sseek() on unopened file(W) You tried to use the seek() or sysseek() function on a filehandle thatwas either never opened or has since been closed.=item select not implemented(F) This machine doesn't implement the select() system call.=item sem%s not implemented(F) You don't have System V semaphore IPC on your system.=item semi-panic: attempt to dup freed string(S) The internal newSVsv() routine was called to duplicate a scalarthat had previously been marked as free.=item Semicolon seems to be missing(W) A nearby syntax error was probably caused by a missing semicolon,or possibly some other missing operator, such as a comma.=item Send on closed socket(W) The filehandle you're sending to got itself closed sometime before now.Check your logic flow.=item Sequence (?#... not terminated(F) A regular expression comment must be terminated by a closingparenthesis.  Embedded parentheses aren't allowed.  See L<perlre>.=item Sequence (?%s...) not implemented(F) A proposed regular expression extension has the character reservedbut has not yet been written.  See L<perlre>.=item Sequence (?%s...) not recognized(F) You used a regular expression extension that doesn't make sense.See L<perlre>.=item Server errorAlso known as "500 Server error".B<This is a CGI error, not a Perl error>.You need to make sure your script is executable, is accessible by the userCGI is running the script under (which is probably not the user account youtested it under), does not rely on any environment variables (like PATH)from the user it isn't running under, and isn't in a location where the CGIserver can't find it, basically, more or less.  Please see the followingfor more information:	http://www.perl.com/perl/faq/idiots-guide.html	http://www.perl.com/perl/faq/perl-cgi-faq.html	ftp://rtfm.mit.edu/pub/usenet/news.answers/www/cgi-faq	http://hoohoo.ncsa.uiuc.edu/cgi/interface.html	http://www-genome.wi.mit.edu/WWW/faqs/www-security-faq.html=item setegid() not implemented(F) You tried to assign to C<$)>, and your operating system doesn't supportthe setegid() system call (or equivalent), or at least Configure didn'tthink so.=item seteuid() not implemented(F) You tried to assign to C<$E<gt>>, and your operating system doesn't supportthe seteuid() system call (or equivalent), or at least Configure didn'tthink so.=item setrgid() not implemented(F) You tried to assign to C<$(>, and your operating system doesn't supportthe setrgid() system call (or equivalent), or at least Configure didn'tthink so.=item setruid() not implemented(F) You tried to assign to C<$<lt>>, and your operating system doesn't supportthe setruid() system call (or equivalent), or at least Configure didn'tthink so.=item Setuid/gid script is writable by world(F) The setuid emulator won't run a script that is writable by the world,because the world might have written on it already.=item shm%s not implemented(F) You don't have System V shared memory IPC on your system.=item shutdown() on closed fd(W) You tried to do a shutdown on a closed socket.  Seems a bit superfluous.=item SIG%s handler "%s" not defined(W) The signal handler named in %SIG doesn't, in fact, exist.  Perhaps youput it into the wrong package?=item sort is now a reserved word(F) An ancient error message that almost nobody ever runs into anymore.But before sort was a keyword, people sometimes used it as a filehandle.=item Sort subroutine didn't return a numeric value(F) A sort comparison routine must return a number.  You probably blewit by not using C<E<lt>=E<gt>> or C<cmp>, or by not using them correctly.See L<perlfunc/sort>.=item Sort subroutine didn't return single value(F) A sort comparison subroutine may not return a list value with moreor less than one element.  See L<perlfunc/sort>.=item Split loop(P) The split was looping infinitely.  (Obviously, a split shouldn't iteratemore times than there are characters of input, which is what happened.)See L<perlfunc/split>.=item Stat on unopened file E<lt>%sE<gt>(W) You tried to use the stat() function (or an equivalent file test)on a filehandle that was either never opened or has since been closed.=item Statement unlikely to be reached(W) You did an exec() with some statement after it other than a die().This is almost always an error, because exec() never returns unlessthere was a failure.  You probably wanted to use system() instead,which does return.  To suppress this warning, put the exec() in a blockby itself.=item Stub found while resolving method `%s' overloading `%s' in package `%s'(P) Overloading resolution over @ISA tree may be broken by importation stubs.Stubs should never be implicitely created, but explicit calls to C<can>may break this.=item Subroutine %s redefined(W) You redefined a subroutine.  To suppress this warning, say    {	local $^W = 0;	eval "sub name { ... }";    }=item Substitution loop(P) The substitution was looping infinitely.  (Obviously, asubstitution shouldn't iterate more times than there are characters ofinput, which is what happened.)  See the discussion of substitution inL<perlop/"Quote and Quote-like Operators">.=item Substitution pattern not terminated(F) The lexer couldn't find the interior delimiter of a s/// or s{}{}construct.  Remember that bracketing delimiters count nesting level.=item Substitution replacement not terminated(F) The lexer couldn't find the final delimiter of a s/// or s{}{}construct.  Remember that bracketing delimiters count nesting level.=item substr outside of string(W) You tried to reference a substr() that pointed outside of a string.That is, the absolute value of the offset was larger than the length ofthe string.  See L<perlfunc/substr>.=item suidperl is no longer needed since %s(F) Your Perl was compiled with B<-D>SETUID_SCRIPTS_ARE_SECURE_NOW, but aversion of the setuid emulator somehow got run anyway.=item syntax error(F) Probably means you had a syntax error.  Common reasons include:    A keyword is misspelled.    A semicolon is missing.    A comma is missing.    An opening or closing parenthesis is missing.    An opening or closing brace is missing.    A closing quote is missing.Often there will be another error message associated with the syntaxerror giving more information.  (Sometimes it helps to turn on B<-w>.)The error message itself often tells you where it was in the line whenit decided to give up.  Sometimes the actual error is several tokensbefore this, because Perl is good at understanding random input.Occasionally the line number may be misleading, and once in a blue moonthe only way to figure out what's triggering the error is to callC<perl -c> repeatedly, chopping away half the program each time to seeif the error went away.  Sort of the cybernetic version of S<20 questions>.=item syntax error at line %d: `%s' unexpected(A) You've accidentally run your script through the Bourne shellinstead of Perl.  Check the #! line, or manually feed your scriptinto Perl yourself.=item System V IPC is not implemented on this machine(F) You tried to do something with a function beginning with "sem", "shm",or "msg".  See L<perlfunc/semctl>, for example.=item Syswrite on closed filehandle(W) The filehandle you're writing to got itself closed sometime before now.Check your logic flow.=item Target of goto is too deeply nested(F) You tried to use C<goto> to reach a label that was too deeplynested for Perl to reach.  Perl is doing you a favor by refusing.=item tell() on unopened file(W) You tried to use the tell() function on a filehandle that was eithernever opened or has since been closed.=item Test on unopened file E<lt>%sE<gt>(W) You tried to invoke a file test operator on a filehandle that isn'topen.  Check your logic.  See also L<perlfunc/-X>.=item That use of $[ is unsupported(F) Assignment to C<$[> is now strictly circumscribed, and interpreted asa compiler directive.  You may say only one of    $[ = 0;    $[ = 1;    ...    local $[ = 0;    local $[ = 1;    ...This is to prevent the problem of one module changing the array baseout from under another module inadvertently.  See L<perlvar/$[>.=item The %s function is unimplementedThe function indicated isn't implemented on this architecture, accordingto the probings of Configure.=item The crypt() function is unimplemented due to excessive paranoia(F) Configure couldn't find the crypt() function on your machine,probably because your vendor didn't supply it, probably because theythink the U.S. Government thinks it's a secret, or at least that theywill continue to pretend that it is.  And if you quote me on that, Iwill deny it.=item The stat preceding C<-l _> wasn't an lstat(F) It makes no sense to test the current stat buffer for symbolic linkhoodif the last stat that wrote to the stat buffer already went pastthe symlink to get to the real file.  Use an actual filename instead.=item times not implemented(F) Your version of the C library apparently doesn't do times().  I suspectyou're not running on Unix.=item Too few args to syscall(F) There has to be at least one argument to syscall() to specify thesystem call to call, silly dilly.=item Too late for "B<-T>" option(X) The #! line (or local equivalent) in a Perl script contains theB<-T> option, but Perl was not invoked with B<-T> in its command line.This is an error because, by the time Perl discovers a B<-T> in ascript, it's too late to properly taint everything from the environment.So Perl gives up.If the Perl script is being executed as a command using the #!mechanism (or its local equivalent), this error can usually be fixedby editing the #! line so that the B<-T> option is a part of Perl'sfirst argument: e.g. change C<perl -n -T> to C<perl -T -n>.If the Perl script is being executed as C<perl scriptname>, then theB<-T> option must appear on the command line: C<perl -T scriptname>.=item Too late for "-%s" option(X) The #! line (or local equivalent) in a Perl script contains theB<-M> or B<-m> option.  This is an error because B<-M> and B<-m> optionsare not intended for use inside scripts.  Use the C<use> pragma instead.=item Too many ('s=item Too many )'s(A) You've accidentally run your script through B<csh> insteadof Perl.  Check the #! line, or manually feed your script intoPerl yourself.=item Too many args to syscall(F) Perl supports a maximum of only 14 args to syscall().=item Too many arguments for %s(F) The function requires fewer arguments than you specified.=item trailing \ in regexp(F) The regular expression ends with an unbackslashed backslash.  Backslashit.   See L<perlre>.=item Translation pattern not terminated(F) The lexer couldn't find the interior delimiter of a tr/// or tr[][]construct.=item Translation replacement not terminated(F) The lexer couldn't find the final delimiter of a tr/// or tr[][]construct.=item truncate not implemented(F) Your machine doesn't implement a file truncation mechanism thatConfigure knows about.=item Type of arg %d to %s must be %s (not %s)(F) This function requires the argument in that position to be of acertain type.  Arrays must be @NAME or C<@{EXPR}>.  Hashes must be%NAME or C<%{EXPR}>.  No implicit dereferencing is allowed--use the{EXPR} forms as an explicit dereference.  See L<perlref>.=item umask: argument is missing initial 0(W) A umask of 222 is incorrect.  It should be 0222, because octal literalsalways start with 0 in Perl, as in C.=item Unable to create sub named "%s"(F) You attempted to create or access a subroutine with an illegal name.=item Unbalanced context: %d more PUSHes than POPs(W) The exit code detected an internal inconsistency in how many executioncontexts were entered and left.=item Unbalanced saves: %d more saves than restores(W) The exit code detected an internal inconsistency in how manyvalues were temporarily localized.=item Unbalanced scopes: %d more ENTERs than LEAVEs(W) The exit code detected an internal inconsistency in how many blockswere entered and left.=item Unbalanced tmps: %d more allocs than frees(W) The exit code detected an internal inconsistency in how many mortalscalars were allocated and freed.=item Undefined format "%s" called(F) The format indicated doesn't seem to exist.  Perhaps it's really inanother package?  See L<perlform>.=item Undefined sort subroutine "%s" called(F) The sort comparison routine specified doesn't seem to exist.  Perhapsit's in a different package?  See L<perlfunc/sort>.=item Undefined subroutine &%s called(F) The subroutine indicated hasn't been defined, or if it was, ithas since been undefined.=item Undefined subroutine called(F) The anonymous subroutine you're trying to call hasn't been defined,or if it was, it has since been undefined.=item Undefined subroutine in sort(F) The sort comparison routine specified is declared but doesn't seem tohave been defined yet.  See L<perlfunc/sort>.=item Undefined top format "%s" called(F) The format indicated doesn't seem to exist.  Perhaps it's really inanother package?  See L<perlform>.=item unexec of %s into %s failed!(F) The unexec() routine failed for some reason.  See your local FSFrepresentative, who probably put it there in the first place.=item Unknown BYTEORDER(F) There are no byte-swapping functions for a machine with this byte order.=item unmatched () in regexp(F) Unbackslashed parentheses must always be balanced in regularexpressions.  If you're a vi user, the % key is valuable for findingthe matching parenthesis.  See L<perlre>.=item Unmatched right bracket(F) The lexer counted more closing curly brackets (braces) than openingones, so you're probably missing an opening bracket.  As a generalrule, you'll find the missing one (so to speak) near the place you werelast editing.=item unmatched [] in regexp(F) The brackets around a character class must match.  If you wish toinclude a closing bracket in a character class, backslash it or put it first.See L<perlre>.=item Unquoted string "%s" may clash with future reserved word(W) You used a bareword that might someday be claimed as a reserved word.It's best to put such a word in quotes, or capitalize it somehow, or insertan underbar into it.  You might also declare it as a subroutine.=item Unrecognized character %s(F) The Perl parser has no idea what to do with the specified characterin your Perl script (or eval).  Perhaps you tried to run a compressedscript, a binary program, or a directory as a Perl program.=item Unrecognized signal name "%s"(F) You specified a signal name to the kill() function that was not recognized.Say C<kill -l> in your shell to see the valid signal names on your system.=item Unrecognized switch: -%s(F) You specified an illegal option to Perl.  Don't do that.(If you think you didn't do that, check the #! line to see if it'ssupplying the bad switch on your behalf.)=item Unsuccessful %s on filename containing newline(W) A file operation was attempted on a filename, and that operationfailed, PROBABLY because the filename contained a newline, PROBABLYbecause you forgot to chop() or chomp() it off.  See L<perlfunc/chomp>.=item Unsupported directory function "%s" called(F) Your machine doesn't support opendir() and readdir().=item Unsupported function fork(F) Your version of executable does not support forking.Note that under some systems, like OS/2, there may be different flavors ofPerl executables, some of which may support fork, some not. Try changingthe name you call Perl by to C<perl_>, C<perl__>, and so on.=item Unsupported function %s(F) This machines doesn't implement the indicated function, apparently.At least, Configure doesn't think so.=item Unsupported socket function "%s" called(F) Your machine doesn't support the Berkeley socket mechanism, or atleast that's what Configure thought.=item Unterminated E<lt>E<gt> operator(F) The lexer saw a left angle bracket in a place where it was expectinga term, so it's looking for the corresponding right angle bracket, and notfinding it.  Chances are you left some needed parentheses out earlier inthe line, and you really meant a "less than".=item Use of "$$<digit>" to mean "${$}<digit>" is deprecated(D) Perl versions before 5.004 misinterpreted any type marker followedby "$" and a digit.  For example, "$$0" was incorrectly taken to mean"${$}0" instead of "${$0}".  This bug is (mostly) fixed in Perl 5.004.However, the developers of Perl 5.004 could not fix this bug completely,because at least two widely-used modules depend on the old meaning of"$$0" in a string.  So Perl 5.004 still interprets "$$<digit>" in theold (broken) way inside strings; but it generates this message as awarning.  And in Perl 5.005, this special treatment will cease.=item Use of $# is deprecated(D) This was an ill-advised attempt to emulate a poorly defined B<awk> feature.Use an explicit printf() or sprintf() instead.=item Use of $* is deprecated(D) This variable magically turned on multi-line pattern matching, both foryou and for any luckless subroutine that you happen to call.  You shoulduse the new C<//m> and C<//s> modifiers now to do that without the dangerousaction-at-a-distance effects of C<$*>.=item Use of %s in printf format not supported(F) You attempted to use a feature of printf that is accessible fromonly C.  This usually means there's a better way to do it in Perl.=item Use of bare E<lt>E<lt> to mean E<lt>E<lt>"" is deprecated(D) You are now encouraged to use the explicitly quoted form if youwish to use an empty line as the terminator of the here-document.=item Use of implicit split to @_ is deprecated(D) It makes a lot of work for the compiler when you clobber asubroutine's argument list, so it's better if you assign the results ofa split() explicitly to an array (or list).=item Use of inherited AUTOLOAD for non-method %s() is deprecated(D) As an (ahem) accidental feature, C<AUTOLOAD> subroutines are lookedup as methods (using the C<@ISA> hierarchy) even when the subroutines tobe autoloaded were called as plain functions (e.g. C<Foo::bar()>), notas methods (e.g. C<Foo->bar()> or C<$obj->bar()>).This bug will be rectified in Perl 5.005, which will use method lookuponly for methods' C<AUTOLOAD>s.  However, there is a significant baseof existing code that may be using the old behavior.  So, as aninterim step, Perl 5.004 issues an optional warning when non-methodsuse inherited C<AUTOLOAD>s.The simple rule is:  Inheritance will not work when autoloadingnon-methods.  The simple fix for old code is:  In any module that used todepend on inheriting C<AUTOLOAD> for non-methods from a base class namedC<BaseClass>, execute C<*AUTOLOAD = \&BaseClass::AUTOLOAD> during startup.=item Use of %s is deprecated(D) The construct indicated is no longer recommended for use, generallybecause there's a better way to do it, and also because the old way hasbad side effects.=item Use of uninitialized value(W) An undefined value was used as if it were already defined.  It wasinterpreted as a "" or a 0, but maybe it was a mistake.  To suppress thiswarning assign an initial value to your variables.=item Useless use of %s in void context(W) You did something without a side effect in a context that does nothingwith the return value, such as a statement that doesn't return a valuefrom a block, or the left side of a scalar comma operator.  Very oftenthis points not to stupidity on your part, but a failure of Perl to parseyour program the way you thought it would.  For example, you'd get thisif you mixed up your C precedence with Python precedence and said    $one, $two = 1, 2;when you meant to say    ($one, $two) = (1, 2);Another common error is to use ordinary parentheses to construct a listreference when you should be using square or curly brackets, forexample, if you say    $array = (1,2);when you should have said    $array = [1,2];The square brackets explicitly turn a list value into a scalar value,while parentheses do not.  So when a parenthesized list is evaluated ina scalar context, the comma is treated like C's comma operator, whichthrows away the left argument, which is not what you want.  SeeL<perlref> for more on this.=item untie attempted while %d inner references still exist(W) A copy of the object returned from C<tie> (or C<tied>) was stillvalid when C<untie> was called.=item Value of %s can be "0"; test with defined()(W) In a conditional expression, you used <HANDLE>, <*> (glob), C<each()>,or C<readdir()> as a boolean value.  Each of these constructs can return avalue of "0"; that would make the conditional expression false, which isprobably not what you intended.  When using these constructs in conditionalexpressions, test their values with the C<defined> operator.=item Variable "%s" is not imported%s(F) While "use strict" in effect, you referred to a global variablethat you apparently thought was imported from another module, becausesomething else of the same name (usually a subroutine) is exportedby that module.  It usually means you put the wrong funny characteron the front of your variable.=item Variable "%s" may be unavailable(W) An inner (nested) I<anonymous> subroutine is inside a I<named>subroutine, and outside that is another subroutine; and the anonymous(innermost) subroutine is referencing a lexical variable defined inthe outermost subroutine.  For example:   sub outermost { my $a; sub middle { sub { $a } } }If the anonymous subroutine is called or referenced (directly orindirectly) from the outermost subroutine, it will share the variableas you would expect.  But if the anonymous subroutine is called orreferenced when the outermost subroutine is not active, it will seethe value of the shared variable as it was before and during the*first* call to the outermost subroutine, which is probably not whatyou want.In these circumstances, it is usually best to make the middlesubroutine anonymous, using the C<sub {}> syntax.  Perl has specificsupport for shared variables in nested anonymous subroutines; a namedsubroutine in between interferes with this feature.=item Variable "%s" will not stay shared(W) An inner (nested) I<named> subroutine is referencing a lexicalvariable defined in an outer subroutine.When the inner subroutine is called, it will probably see the value ofthe outer subroutine's variable as it was before and during the*first* call to the outer subroutine; in this case, after the firstcall to the outer subroutine is complete, the inner and outersubroutines will no longer share a common value for the variable.  Inother words, the variable will no longer be shared.Furthermore, if the outer subroutine is anonymous and references alexical variable outside itself, then the outer and inner subroutineswill I<never> share the given variable.This problem can usually be solved by making the inner subroutineanonymous, using the C<sub {}> syntax.  When inner anonymous subs thatreference variables in outer subroutines are called or referenced,they are automatically rebound to the current values of suchvariables.=item Variable syntax(A) You've accidentally run your script through B<csh> insteadof Perl.  Check the #! line, or manually feed your script intoPerl yourself.=item Warning: something's wrong(W) You passed warn() an empty string (the equivalent of C<warn "">) oryou called it with no args and C<$_> was empty.=item Warning: unable to close filehandle %s properly(S) The implicit close() done by an open() got an error indication on theclose().  This usually indicates your file system ran out of disk space.=item Warning: Use of "%s" without parentheses is ambiguous(S) You wrote a unary operator followed by something that looks like abinary operator that could also have been interpreted as a term orunary operator.  For instance, if you know that the rand functionhas a default argument of 1.0, and you write    rand + 5;you may THINK you wrote the same thing as    rand() + 5;but in actual fact, you got    rand(+5);So put in parentheses to say what you really mean.=item Write on closed filehandle(W) The filehandle you're writing to got itself closed sometime before now.Check your logic flow.=item X outside of string(F) You had a pack template that specified a relative position beforethe beginning of the string being unpacked.  See L<perlfunc/pack>.=item x outside of string(F) You had a pack template that specified a relative position afterthe end of the string being unpacked.  See L<perlfunc/pack>.=item Xsub "%s" called in sort(F) The use of an external subroutine as a sort comparison is not yet supported.=item Xsub called in sort(F) The use of an external subroutine as a sort comparison is not yet supported.=item You can't use C<-l> on a filehandle(F) A filehandle represents an opened file, and when you opened the file italready went past any symlink you are presumably trying to look for.Use a filename instead.=item YOU HAVEN'T DISABLED SET-ID SCRIPTS IN THE KERNEL YET!(F) And you probably never will, because you probably don't have thesources to your kernel, and your vendor probably doesn't give a ripabout what you want.  Your best bet is to use the wrapsuid script inthe eg directory to put a setuid C wrapper around your script.=item You need to quote "%s"(W) You assigned a bareword as a signal handler name.  Unfortunately, youalready have a subroutine of that name declared, which means that Perl 5will try to call the subroutine when the assignment is executed, which isprobably not what you want.  (If it IS what you want, put an & in front.)=item [gs]etsockopt() on closed fd(W) You tried to get or set a socket option on a closed socket.Did you forget to check the return value of your socket() call?See L<perlfunc/getsockopt>.=item \1 better written as $1(W) Outside of patterns, backreferences live on as variables.  The useof backslashes is grandfathered on the right-hand side of asubstitution, but stylistically it's better to use the variable formbecause other Perl programmers will expect it, and it works betterif there are more than 9 backreferences.=item '|' and 'E<lt>' may not both be specified on command line(F) An error peculiar to VMS.  Perl does its own command line redirection, andfound that STDIN was a pipe, and that you also tried to redirect STDIN using'E<lt>'.  Only one STDIN stream to a customer, please.=item '|' and 'E<gt>' may not both be specified on command line(F) An error peculiar to VMS.  Perl does its own command line redirection, andthinks you tried to redirect stdout both to a file and into a pipe to anothercommand.  You need to choose one or the other, though nothing's stopping youfrom piping into a program or Perl script which 'splits' output into twostreams, such as    open(OUT,">$ARGV[0]") or die "Can't write to $ARGV[0]: $!";    while (<STDIN>) {        print;        print OUT;    }    close OUT;=item Got an error from DosAllocMem(P) An error peculiar to OS/2.  Most probably you're using an obsoleteversion of Perl, and this should not happen anyway.=item Malformed PERLLIB_PREFIX(F) An error peculiar to OS/2.  PERLLIB_PREFIX should be of the form    prefix1;prefix2or    prefix1 prefix2with nonempty prefix1 and prefix2.  If C<prefix1> is indeed a prefixof a builtin library search path, prefix2 is substituted.  The errormay appear if components are not found, or are too long.  See"PERLLIB_PREFIX" in F<README.os2>.=item PERL_SH_DIR too long(F) An error peculiar to OS/2. PERL_SH_DIR is the directory to find theC<sh>-shell in.  See "PERL_SH_DIR" in F<README.os2>.=item Process terminated by SIG%s(W) This is a standard message issued by OS/2 applications, while *nixapplications die in silence.  It is considered a feature of the OS/2port.  One can easily disable this by appropriate sighandlers, seeL<perlipc/"Signals">.  See also "Process terminated by SIGTERM/SIGINT"in F<README.os2>.=back