my $pid1 = open( my $fh1, '|-');
if ( $pid1 == 0 )
{
    print "child1 sez: $$ forked, now exec()ing false!!\n";
    exec (qw/false/) or die "Can't exec false $!";
}

my $pid2 = open( my $fh2, '|-');
if ( $pid2 == 0 )
{
    print "child2 sez: $$ forked, now exec()ing true!!\n";
    exec (qw/true/) or die "Can't exec false $!";
}

sleep 1; # just so the output makes more sense
print "Hi, I'm the parent, and I'm going to wait for pid1=($pid1) and 
+pid2=($pid2)!\n";

my $dead_pid;
$dead_pid = waitpid $pid1, 0;
print "parent sez: pid $dead_pid exited with status $?\n";
$dead_pid = waitpid $pid2, 0;
print "parent sez: pid $dead_pid exited with status $?\n";

[download]

Output is:

child1 sez: 19628 forked, now exec()ing false!!
child2 sez: 19629 forked, now exec()ing true!!
Hi, I'm the parent, and I'm going to wait for pid1=(19628) and pid2=(1
+9629)!
parent sez: pid 19628 exited with status 256
parent sez: pid 19629 exited with status 0

[download]
--
edan

In reply to Re^3: multi-command sytem call by edan
in thread multi-command sytem call by water

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