show follow-fork-mode
Debugger response to a program call of fork or vfork is "parent".
set follow-fork-mode mode
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.
show detach-on-fork
Whether gdb will detach the child of a fork is on.
set detach-on-fork mode
on
The child process (or parent process, depending on the value of follow-fork-mode) will be detached and allowed to run independently. This is the default.
off
Both processes will be held under the control of GDB. One process (child or parent, depending on the value of follow-fork-mode) is debugged as usual, while the other is held suspended.
| follow-fork-mode |
detach-on-fork |
result |
| parent |
on |
debug parent process |
| child |
on |
debug first child process |
| parent |
off |
after fork() all child processes will be blocked, parent |
| child |
off |
after fork() first child process will be created, parent process will be bolcked on fork(), the inferior will on child process, when switch to parent process and continue running fork(), another child process will be created |
info inferiors
Num Description Executable
1 process 17027 exe1
* 2 process 17028 exe1
inferior 1
[Switching to inferior 1 .......
4.11 Debugging Forks
See also