Skunkware 5/Skunkware 5.iso/man/cat.1/gdb.1

Text File | 1995-07-26 | 12.3 KB | 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:




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          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



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          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



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          ----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.




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          ----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.






















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