As I have talked in YAPC::Asia couple of years ago, the wait functions (e.g. wait, waitpid) of Perl do not return EINTR when receiving a signal. This is a problem if you would want to wait for child processes until receiving a signal. Proc::Wait3 can be a solution, however the module may be hard to install as it is an XS module. It should also be noted that the module provides replacement for wait