diff options
| author | Nicholas Clark <nick@ccl4.org> | 2001-09-10 23:00:40 +0100 |
|---|---|---|
| committer | Jarkko Hietaniemi <jhi@iki.fi> | 2001-09-10 23:24:11 +0000 |
| commit | 816229cf4a3690b9abc75d05aaabf5930497cf24 (patch) | |
| tree | a60f04709ccdcb27604bc22d8dfff362ecf0a313 /pod/perlipc.pod | |
| parent | e83d50c9254af4011034b5ec3368b06bb6254055 (diff) | |
| download | perl-816229cf4a3690b9abc75d05aaabf5930497cf24.tar.gz | |
avoiding hoardes of zombies
Message-ID: <20010910220040.C1512@plum.flirble.org>
p4raw-id: //depot/perl@11987
Diffstat (limited to 'pod/perlipc.pod')
| -rw-r--r-- | pod/perlipc.pod | 20 |
1 files changed, 15 insertions, 5 deletions
diff --git a/pod/perlipc.pod b/pod/perlipc.pod index a1df3e42e0..56816b15d6 100644 --- a/pod/perlipc.pod +++ b/pod/perlipc.pod @@ -121,11 +121,15 @@ signal handlers like this: $SIG{CHLD} = \&REAPER; # now do something that forks... -or even the more elaborate: +or better still: use POSIX ":sys_wait_h"; sub REAPER { my $child; + # If a second child dies while in the signal handler caused by the + # first death, we won't get another signal. So must loop here else + # we will leave the unreaped child as a zombie. And the next time + # two children die we get another zombie. And so on. while (($child = waitpid(-1,WNOHANG)) > 0) { $Kid_Status{$child} = $?; } @@ -724,10 +728,13 @@ go back to service a new client. my $waitedpid = 0; my $paddr; + use POSIX ":sys_wait_h"; sub REAPER { - $waitedpid = wait; + my $child; + while (($waitedpid = waitpid(-1,WNOHANG)) > 0) { + logmsg "reaped $waitedpid" . ($? ? " with exit $?" : ''); + } $SIG{CHLD} = \&REAPER; # loathe sysV - logmsg "reaped $waitedpid" . ($? ? " with exit $?" : ''); } $SIG{CHLD} = \&REAPER; @@ -881,10 +888,13 @@ to be on the localhost, and thus everything works right. my $waitedpid; + use POSIX ":sys_wait_h"; sub REAPER { - $waitedpid = wait; + my $child; + while (($waitedpid = waitpid(-1,WNOHANG)) > 0) { + logmsg "reaped $waitedpid" . ($? ? " with exit $?" : ''); + } $SIG{CHLD} = \&REAPER; # loathe sysV - logmsg "reaped $waitedpid" . ($? ? " with exit $?" : ''); } $SIG{CHLD} = \&REAPER; |