In this code below, when I am fork ing, depending on the $pid value the if and elsif should be executed, but here I see that the print statement in the if block is also getting satisfied alongwith the elsif block which calls the sub1 ().
Can anybody please explain ?


use strict;
use warnings;

print "Starting main program\n";
my @childs;

for ( my $count = 1; $count <= 3 ; $count++) {
my $pid = fork();
if ($pid) {
# parent
print "pid is $pid, parent $$\n";
push(@childs, $pid);
} elsif ($pid == 0) {
# child
sub1($count);
exit 0;
} else {
die "couldnt fork: $!\n";
}



}

foreach (@childs) {
my $tmp = waitpid($_, 0);
print "done with pid $tmp\n";

}

print "End of main program\n";


sub sub1 {
my $num = shift;
print "started child process for $num\n";
sleep $num;
print "done with child process for $num\n";
return $num;
}

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In reply to how come both the if and elsif block getting executed ? by ghosh123

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