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IRIX Base Documentation 1998 November
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IRIX 6.5.2 Base Documentation November 1998.img
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1998-10-30
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133 lines
ssssccccaaaannnn((((3333TTTTccccllll)))) ssssccccaaaannnn((((3333TTTTccccllll))))
NNNNAAAAMMMMEEEE
scan - Parse string using conversion specifiers in the style of sscanf
SSSSYYYYNNNNOOOOPPPPSSSSIIIISSSS
ssssccccaaaannnn _s_t_r_i_n_g _f_o_r_m_a_t _v_a_r_N_a_m_e ?_v_a_r_N_a_m_e ...?
IIIINNNNTTTTRRRROOOODDDDUUUUCCCCTTTTIIIIOOOONNNN
This command parses fields from an input string in the same fashion as
the ANSI C ssssssssccccaaaannnnffff procedure and returns a count of the number of |
conversions performed, or -1 if the end of the input string is reached |
before any conversions have been performed. _S_t_r_i_n_g gives the input to be
parsed and _f_o_r_m_a_t indicates how to parse it, using %%%% conversion
specifiers as in ssssssssccccaaaannnnffff. Each _v_a_r_N_a_m_e gives the name of a variable; when
a field is scanned from _s_t_r_i_n_g the result is converted back into a string
and assigned to the corresponding variable.
DDDDEEEETTTTAAAAIIIILLLLSSSS OOOONNNN SSSSCCCCAAAANNNNNNNNIIIINNNNGGGG
SSSSccccaaaannnn operates by scanning _s_t_r_i_n_g and _f_o_r_m_a_t_S_t_r_i_n_g together. If the next
character in _f_o_r_m_a_t_S_t_r_i_n_g is a blank or tab then it matches any number of
white space characters in _s_t_r_i_n_g (including zero). Otherwise, if it
isn't a %%%% character then it must match the next character of _s_t_r_i_n_g.
When a %%%% is encountered in _f_o_r_m_a_t_S_t_r_i_n_g, it indicates the start of a
conversion specifier. A conversion specifier contains three fields after
the %%%%: a ****, which indicates that the converted value is to be discarded
instead of assigned to a variable; a number indicating a maximum field
width; and a conversion character. All of these fields are optional
except for the conversion character.
When ssssccccaaaannnn finds a conversion specifier in _f_o_r_m_a_t_S_t_r_i_n_g, it first skips
any white-space characters in _s_t_r_i_n_g. Then it converts the next input
characters according to the conversion specifier and stores the result in
the variable given by the next argument to ssssccccaaaannnn. The following
conversion characters are supported:
dddd The input field must be a decimal integer. It is read in and
the value is stored in the variable as a decimal string.
oooo The input field must be an octal integer. It is read in and the
value is stored in the variable as a decimal string.
xxxx The input field must be a hexadecimal integer. It is read in
and the value is stored in the variable as a decimal string.
cccc A single character is read in and its binary value is stored in
the variable as a decimal string. Initial white space is not
skipped in this case, so the input field may be a white-space
character. This conversion is different from the ANSI standard
in that the input field always consists of a single character
and no field width may be specified.
PPPPaaaaggggeeee 1111
ssssccccaaaannnn((((3333TTTTccccllll)))) ssssccccaaaannnn((((3333TTTTccccllll))))
ssss The input field consists of all the characters up to the next
white-space character; the characters are copied to the
variable.
eeee or ffff or gggg
The input field must be a floating-point number consisting of
an optional sign, a string of decimal digits possibly
containing a decimal point, and an optional exponent consisting
of an eeee or EEEE followed by an optional sign and a string of
decimal digits. It is read in and stored in the variable as a
floating-point string.
[[[[_c_h_a_r_s]]]] The input field consists of any number of characters in _c_h_a_r_s.
The matching string is stored in the variable. If the first
character between the brackets is a ]]]] then it is treated as
part of _c_h_a_r_s rather than the closing bracket for the set.
[[[[^^^^_c_h_a_r_s]]]] The input field consists of any number of characters not in
_c_h_a_r_s. The matching string is stored in the variable. If the
character immediately following the ^^^^ is a ]]]] then it is treated
as part of the set rather than the closing bracket for the set.
The number of characters read from the input for a conversion is the
largest number that makes sense for that particular conversion (e.g. as
many decimal digits as possible for %%%%dddd, as many octal digits as possible
for %%%%oooo, and so on). The input field for a given conversion terminates
either when a white-space character is encountered or when the maximum
field width has been reached, whichever comes first. If a **** is present
in the conversion specifier then no variable is assigned and the next
scan argument is not consumed.
DDDDIIIIFFFFFFFFEEEERRRREEEENNNNCCCCEEEESSSS FFFFRRRROOOOMMMM AAAANNNNSSSSIIII SSSSSSSSCCCCAAAANNNNFFFF
The behavior of the ssssccccaaaannnn command is the same as the behavior of the ANSI
C ssssssssccccaaaannnnffff procedure except for the following differences:
[1] %%%%pppp and %%%%nnnn conversion specifiers are not currently supported. |
[2] For %%%%cccc conversions a single character value is converted to a
decimal string, which is then assigned to the corresponding _v_a_r_N_a_m_e;
no field width may be specified for this conversion.
[3] The llll, hhhh, and LLLL modifiers are ignored; integer values are always |
converted as if there were no modifier present and real values are |
always converted as if the llll modifier were present (i.e. type ddddoooouuuubbbblllleeee|
is used for the internal representation).
KKKKEEEEYYYYWWWWOOOORRRRDDDDSSSS
conversion specifier, parse, scan
PPPPaaaaggggeeee 2222