home
***
CD-ROM
|
disk
|
FTP
|
other
***
search
/
SGI Freeware 1998 November
/
Freeware November 1998.img
/
dist
/
fw_gdb.idb
/
usr
/
freeware
/
catman
/
u_man
/
cat1
/
gdb.Z
/
gdb
Wrap
Text File
|
1998-10-27
|
11KB
|
331 lines
ggggddddbbbb((((1111)))) GGGGNNNNUUUU TTTToooooooollllssss ((((4444nnnnoooovvvv1111999999991111)))) ggggddddbbbb((((1111))))
NNNNAAAAMMMMEEEE
gdb - The GNU Debugger
SSSSYYYYNNNNOOOOPPPPSSSSIIIISSSS
ggggddddbbbb [----hhhheeeellllpppp] [----nnnnxxxx] [----qqqq] [----bbbbaaaattttcccchhhh] [----ccccdddd====_d_i_r] [----ffff] [----bbbb _b_p_s]
[----ttttttttyyyy====_d_e_v] [----ssss _s_y_m_f_i_l_e] [----eeee _p_r_o_g] [----sssseeee _p_r_o_g] [----cccc _c_o_r_e]
[----xxxx _c_m_d_s] [----dddd _d_i_r] [_p_r_o_g[_c_o_r_e|_p_r_o_c_I_D]]
DDDDEEEESSSSCCCCRRRRIIIIPPPPTTTTIIIIOOOONNNN
The purpose of a debugger such as GDB is to allow you to see
what is going on ``inside'' another program while it
executes-or what another program was doing at the moment it
crashed.
GDB can do four main kinds of things (plus other things in
support of these) to help you catch bugs in the act:
+o Start your program, specifying anything that might
affect its behavior.
+o Make your program stop on specified conditions.
+o Examine what has happened, when your program has
stopped.
+o Change things in your program, so you can experiment
with correcting the effects of one bug and go on to
learn about another.
You can use GDB to debug programs written in C, C++, and
Modula-2. Fortran support will be added when a GNU Fortran
compiler is ready.
GDB is invoked with the shell command ggggddddbbbb. Once started, it
reads commands from the terminal until you tell it to exit
with the GDB command qqqquuuuiiiitttt. You can get online help from ggggddddbbbb
itself by using the command hhhheeeellllpppp.
You can run ggggddddbbbb with no arguments or options; but the most
usual way to start GDB is with one argument or two,
specifying an executable program as the argument:
gdb program
You can also start with both an executable program and a
core file specified:
Page 1 (printed 10/22/98)
ggggddddbbbb((((1111)))) GGGGNNNNUUUU TTTToooooooollllssss ((((4444nnnnoooovvvv1111999999991111)))) ggggddddbbbb((((1111))))
gdb program core
You can, instead, specify a process ID as a second argument,
if you want to debug a running process:
gdb program 1234
would attach GDB to process 1111222233334444 (unless you also have a
file named `1111222233334444'; GDB does check for a core file first).
Here are some of the most frequently needed GDB commands:
bbbbrrrreeeeaaaakkkk [_f_i_l_e::::]_f_u_n_c_t_i_o_n
Set a breakpoint at _f_u_n_c_t_i_o_n (in _f_i_l_e).
rrrruuuunnnn [_a_r_g_l_i_s_t]
Start your program (with _a_r_g_l_i_s_t, if specified).
bbbbtttt Backtrace: display the program stack.
pppprrrriiiinnnntttt _e_x_p_r
Display the value of an expression.
cccc Continue running your program (after stopping, e.g. at
a breakpoint).
nnnneeeexxxxtttt Execute next program line (after stopping); step _o_v_e_r
any function calls in the line.
sssstttteeeepppp Execute next program line (after stopping); step _i_n_t_o
any function calls in the line.
hhhheeeellllpppp [_n_a_m_e]
Show information about GDB command _n_a_m_e, or general
information about using GDB.
qqqquuuuiiiitttt Exit from GDB.
For full details on GDB, see _U_s_i_n_g _G_D_B: _A _G_u_i_d_e _t_o _t_h_e _G_N_U
_S_o_u_r_c_e-_L_e_v_e_l _D_e_b_u_g_g_e_r, by Richard M. Stallman and Roland H.
Pesch. The same text is available online as the ggggddddbbbb entry
in the iiiinnnnffffoooo program.
OOOOPPPPTTTTIIIIOOOONNNNSSSS
Any arguments other than options specify an executable file
and core file (or process ID); that is, the first argument
encountered with no associated option flag is equivalent to
a `----sssseeee' option, and the second, if any, is equivalent to a
`----cccc' option if it's the name of a file. Many options have
both long and short forms; both are shown here. The long
Page 2 (printed 10/22/98)
ggggddddbbbb((((1111)))) GGGGNNNNUUUU TTTToooooooollllssss ((((4444nnnnoooovvvv1111999999991111)))) ggggddddbbbb((((1111))))
forms are also recognized if you truncate them, so long as
enough of the option is present to be unambiguous. (If you
prefer, you can flag option arguments with `++++' rather than
`----', though we illustrate the more usual convention.)
All the options and command line arguments you give are
processed in sequential order. The order makes a difference
when the `----xxxx' option is used.
----hhhheeeellllpppp
----hhhh List all options, with brief explanations.
----ssssyyyymmmmbbbboooollllssss====_f_i_l_e
----ssss _f_i_l_e
Read symbol table from file _f_i_l_e.
----eeeexxxxeeeecccc====_f_i_l_e
----eeee _f_i_l_e
Use file _f_i_l_e as the executable file to execute when
appropriate, and for examining pure data in conjunction
with a core dump.
----sssseeee====_f_i_l_e
Read symbol table from file _f_i_l_e and use it as the
executable file.
----ccccoooorrrreeee====_f_i_l_e
----cccc _f_i_l_e
Use file _f_i_l_e as a core dump to examine.
----ccccoooommmmmmmmaaaannnndddd====_f_i_l_e
----xxxx _f_i_l_e
Execute GDB commands from file _f_i_l_e.
----ddddiiiirrrreeeeccccttttoooorrrryyyy====_d_i_r_e_c_t_o_r_y
----dddd _d_i_r_e_c_t_o_r_y
Add _d_i_r_e_c_t_o_r_y to the path to search for source files.
----nnnnxxxx
Page 3 (printed 10/22/98)
ggggddddbbbb((((1111)))) GGGGNNNNUUUU TTTToooooooollllssss ((((4444nnnnoooovvvv1111999999991111)))) ggggddddbbbb((((1111))))
----nnnn Do not execute commands from any `....ggggddddbbbbiiiinnnniiiitttt'
initialization files. Normally, the commands in these
files are executed after all the command options and
arguments have been processed.
----qqqquuuuiiiieeeetttt
----qqqq ``Quiet''. Do not print the introductory and copyright
messages. These messages are also suppressed in batch
mode.
----bbbbaaaattttcccchhhh
Run in batch mode. Exit with status 0000 after processing
all the command files specified with `----xxxx' (and
`....ggggddddbbbbiiiinnnniiiitttt', if not inhibited). Exit with nonzero
status if an error occurs in executing the GDB commands
in the command files.
Batch mode may be useful for running GDB as a filter,
for example to download and run a program on another
computer; in order to make this more useful, the
message
Program exited normally.
(which is ordinarily issued whenever a program running
under GDB control terminates) is not issued when
running in batch mode.
----ccccdddd====_d_i_r_e_c_t_o_r_y
Run GDB using _d_i_r_e_c_t_o_r_y as its working directory,
instead of the current directory.
----ffffuuuullllllllnnnnaaaammmmeeee
----ffff Emacs sets this option when it runs GDB as a
subprocess. It tells GDB to output the full file name
and line number in a standard, recognizable fashion
each time a stack frame is displayed (which includes
each time the program stops). This recognizable format
looks like two ` 33332222' characters, followed by the file
name, line number and character position separated by
colons, and a newline. The Emacs-to-GDB interface
program uses the two ` 33332222' characters as a signal to
display the source code for the frame.
Page 4 (printed 10/22/98)
ggggddddbbbb((((1111)))) GGGGNNNNUUUU TTTToooooooollllssss ((((4444nnnnoooovvvv1111999999991111)))) ggggddddbbbb((((1111))))
----bbbb _b_p_s
Set the line speed (baud rate or bits per second) of
any serial interface used by GDB for remote debugging.
----ttttttttyyyy====_d_e_v_i_c_e
Run using _d_e_v_i_c_e for your program's standard input and
output.
SSSSEEEEEEEE AAAALLLLSSSSOOOO
`ggggddddbbbb' entry in iiiinnnnffffoooo; _U_s_i_n_g _G_D_B: _A _G_u_i_d_e _t_o _t_h_e _G_N_U _S_o_u_r_c_e-
_L_e_v_e_l _D_e_b_u_g_g_e_r, Richard M. Stallman and Roland H. Pesch,
July 1991.
CCCCOOOOPPPPYYYYIIIINNNNGGGG
Copyright (c) 1991 Free Software Foundation, Inc.
Permission is granted to make and distribute verbatim copies
of this manual provided the copyright notice and this
permission notice are preserved on all copies.
Permission is granted to copy and distribute modified
versions of this manual under the conditions for verbatim
copying, provided that the entire resulting derived work is
distributed under the terms of a permission notice identical
to this one.
Permission is granted to copy and distribute translations of
this manual into another language, under the above
conditions for modified versions, except that this
permission notice may be included in translations approved
by the Free Software Foundation instead of in the original
English.
Page 5 (printed 10/22/98)