How can I switch between different processes fork() ed in gdb?

Question

I\'m debugging such a multiple process application,

how can I switch between the fork()ed processes?

Answer 1

Show all the processes.

(gdb) info inferiors 
  Num  Description       Executable        
  1    process 1000      /tmp/a.out 
* 2                /tmp/a.out  # current attach inferior

Switch between different processes.

(gdb) inferior 1
[Switching to inferior 1 [process 1000] (/tmp/a.out)]
[Switching to thread 1.1 (LWP 1000)]