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#!/usr/bin/perl
eval 'exec /usr/bin/perl -S $0 ${1+"$@"}'
if $running_under_some_shell;
require 'sys/ipc.ph';
require 'sys/msg.ph';
$| = 1;
$mode = shift;
die "usage: ipcmsg {r|s}\n" unless $mode =~ /^[rs]$/;
$send = ($mode eq "s");
$id = msgget(0x1234, ($send ? 0 : &IPC_CREAT) | 0644);
die "Can't get message queue: $!\n" unless defined($id);
print "message queue id: $id\n";
if ($send) {
while (<STDIN>) {
chop;
unless (msgsnd($id, pack("LA*", $., $_), 0)) {
die "Can't send message: $!\n";
}
}
}
else {
$SIG{'INT'} = $SIG{'QUIT'} = "leave";
for (;;) {
unless (msgrcv($id, $_, 512, 0, 0)) {
die "Can't receive message: $!\n";
}
($type, $message) = unpack("La*", $_);
printf "[%d] %s\n", $type, $message;
}
}
&leave;
sub leave {
if (!$send) {
$x = msgctl($id, &IPC_RMID, 0);
if (!defined($x) || $x < 0) {
die "Can't remove message queue: $!\n";
}
}
exit;
}
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