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(libtool14.info.gz) Debugging executables

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 3.4 Debugging executables
 =========================
 
 If `hell' was a complicated program, you would certainly want to test
 and debug it before installing it on your system.  In the above
 section, you saw how the libtool wrapper script makes it possible to run
 the program directly, but unfortunately, this mechanism interferes with
 the debugger:
 
      burger$ gdb hell
      GDB is free software and you are welcome to distribute copies of it
       under certain conditions; type "show copying" to see the conditions.
      There is no warranty for GDB; type "show warranty" for details.
      GDB 4.16 (i386-unknown-netbsd), (C) 1996 Free Software Foundation, Inc.
 
      "hell": not in executable format: File format not recognized
 
      (gdb) quit
      burger$
 
    Sad.  It doesn't work because GDB doesn't know where the executable
 lives.  So, let's try again, by invoking GDB directly on the executable:
 
      burger$ gdb .libs/hell
      trick:/home/src/libtool/demo$ gdb .libs/hell
      GDB is free software and you are welcome to distribute copies of it
       under certain conditions; type "show copying" to see the conditions.
      There is no warranty for GDB; type "show warranty" for details.
      GDB 4.16 (i386-unknown-netbsd), (C) 1996 Free Software Foundation, Inc.
      (gdb) break main
      Breakpoint 1 at 0x8048547: file main.c, line 29.
      (gdb) run
      Starting program: /home/src/libtool/demo/.libs/hell
      /home/src/libtool/demo/.libs/hell: can't load library 'libhello.so.2'
 
      Program exited with code 020.
      (gdb) quit
      burger$
 
    Argh.  Now GDB complains because it cannot find the shared library
 that `hell' is linked against.  So, we must use libtool in order to
 properly set the library path and run the debugger.  Fortunately, we can
 forget all about the `.libs' directory, and just run it on the
 executable wrapper ( Execute mode):
 
      burger$ libtool gdb hell
      GDB is free software and you are welcome to distribute copies of it
       under certain conditions; type "show copying" to see the conditions.
      There is no warranty for GDB; type "show warranty" for details.
      GDB 4.16 (i386-unknown-netbsd), (C) 1996 Free Software Foundation, Inc.
      (gdb) break main
      Breakpoint 1 at 0x8048547: file main.c, line 29.
      (gdb) run
      Starting program: /home/src/libtool/demo/.libs/hell
 
      Breakpoint 1, main (argc=1, argv=0xbffffc40) at main.c:29
      29	  printf ("Welcome to GNU Hell!\n");
      (gdb) quit
      The program is running.  Quit anyway (and kill it)? (y or n) y
      burger$
 
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