How do I debug the child process after fork() in gdb?

Question

After calling fork, the current process will call exit(0).

But the child will continue.

switch(fork())
{
  case -1:
    exit(1);
  case 0:
    // child process continues
    break;
  default:
    // the current process exits
    exit(0);
}

How can I continue debugging the child process in this case?

For `exec`: http://stackoverflow.com/questions/377195/how-to-debug-the-entry-point-of-fork-exec-process/43099366#43099366 — Ciro Santilli OurBigBook.com, Mar 29 '17 at 16:39

score 51 · Accepted Answer · edited Oct 29 '13 at 12:50

51

Look at this. Use:

set follow-fork-mode <mode>

Set the debugger response to a program call of fork or vfork. A call to fork or vfork creates a new process. The <mode> argument can be:

parent: The original process is debugged after a fork. The child process runs unimpeded. This is the default.

child: The new process is debugged after a fork. The parent process runs unimpeded.

edited Oct 29 '13 at 12:50

Stefan

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answered Jun 01 '11 at 09:51

Mihran Hovsepyan

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Is there a way debug both parent and child? – Bin Zhou Mar 03 '22 at 08:39

How do I debug the child process after fork() in gdb?

1 Answers1

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