Integrate perlio:
Jarkko Hietaniemi [Mon, 17 Dec 2001 16:43:09 +0000 (16:43 +0000)]
[ 13724]
Fix for alarm() breaking into wait*().
Call PERL_ASYNC_CHECK() on EINTR in Perl_wait4pid(), to dispatch
signal handler before caller re-does the system call.

p4raw-link: @13724 on //depot/perlio: cddd4526476ba0ae3c81876684c5e7a648cb3265

p4raw-id: //depot/perl@13725


Trivial merge