GDB 主要调试命令

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:]functiop
       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
   available online  as the "gdb" entry in the "info" program.