gdb 文档
[root@rockylinux src]# gcc -g -o cpp_test cpp_test.cpp -lstdc++ // 若用“gdb”调试程序，在程序编译时，必须启用选项“-g”。
[root@rockylinux src]# man gdb
GDB(1) GNU Development Tools GDB(1)
NAME
gdb - The GNU Debugger
SYNOPSIS
gdb [-help] [-nh] [-nx] [-q] [-batch] [-cd=dir] [-f] [-b bps]
[-tty=dev] [-s symfile] [-e prog] [-se prog] [-c core] [-p procID]
[-x cmds] [-d dir] [prog|prog procID|prog core]
DESCRIPTION
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:
· Start your program, specifying anything that might affect its behavior.
· Make your program stop on specified conditions.
· Examine what has happened, when your program has stopped.
· 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@t{++}, Fortran and Modula-2.
GDB is invoked with the shell command "gdb". Once started, it reads commands
from the terminal until you tell it to exit with the GDB command "quit". You
can get online help from GDB itself by using the command "help".
You can run "gdb" 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:
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
gdb -p 1234
would attach GDB to process 1234 (unless you also have a file named 1234; GDB
does check for a core file first). With option -p you can omit the program
filename.
Here are some of the most frequently needed GDB commands:
break [file:]function
Set a breakpoint at function (in file).
run [arglist]
Start your program (with arglist, if specified).
bt Backtrace: display the program stack.
print expr
Display the value of an expression.
c Continue running your program (after stopping, e.g. at a breakpoint).
next
Execute next program line (after stopping); step over any function calls in
the line.
edit [file:]function
look at the program line where it is presently stopped.
list [file:]function
type the text of the program in the vicinity of where it is presently
stopped.
step
Execute next program line (after stopping); step into any function calls in
the line.
help [name]
Show information about GDB command name, or general information about using
GDB.
quit
Exit from GDB.
For full details on GDB, see Using GDB: A Guide to the GNU Source-Level
Debugger, by Richard M. Stallman and Roland H. Pesch. The same text is
available online as the "gdb" entry in the "info" program.
OPTIONS
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 -se option, and the second, if any, is equivalent to a
-c option if it's the name of a file. Many options have both long and short
forms; both are shown here. The long 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 -x option is used.
-help
-h List all options, with brief explanations.
-symbols=file
-s file
Read symbol table from file file.
-write
Enable writing into executable and core files.
-exec=file
-e file
Use file file as the executable file to execute when appropriate, and for
examining pure data in conjunction with a core dump.
-se=file
Read symbol table from file file and use it as the executable file.
-core=file
-c file
Use file file as a core dump to examine.
-command=file
-x file
Execute GDB commands from file file.
-ex command
Execute given GDB command.
-directory=directory
-d directory
Add directory to the path to search for source files.
-nh Do not execute commands from ~/.gdbinit.
-nx
-n Do not execute commands from any .gdbinit initialization files.
-quiet
-q "Quiet". Do not print the introductory and copyright messages. These
messages are also suppressed in batch mode.
-batch
Run in batch mode. Exit with status 0 after processing all the command
files specified with -x (and .gdbinit, 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.
-cd=directory
Run GDB using directory as its working directory, instead of the current
directory.
-fullname
-f 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 \032 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
\032 characters as a signal to display the source code for the frame.
-b bps
Set the line speed (baud rate or bits per second) of any serial interface
used by GDB for remote debugging.
-tty=device
Run using device for your program's standard input and output.
SEE ALSO
The full documentation for GDB is maintained as a Texinfo manual. If the
"info" and "gdb" programs and GDB's Texinfo documentation are properly
installed at your site, the command
info gdb
should give you access to the complete manual.
Using GDB: A Guide to the GNU Source-Level Debugger, Richard M. Stallman and
Roland H. Pesch, July 1991.
COPYRIGHT
Copyright (c) 1988-2018 Free Software Foundation, Inc.
Permission is granted to copy, distribute and/or modify this document under the
terms of the GNU Free Documentation License, Version 1.3 or any later version
published by the Free Software Foundation; with the Invariant Sections being
"Free Software" and "Free Software Needs Free Documentation", with the Front-
Cover Texts being "A GNU Manual," and with the Back-Cover Texts as in (a)
below.
(a) The FSF's Back-Cover Text is: "You are free to copy and modify this GNU
Manual. Buying copies from GNU Press supports the FSF in developing GNU and
promoting software freedom."
gdb-Red Hat Enterprise Linux 8.2-16.el2021-10-11 GDB(1)