use strict;
use warnings;

use constant FORK_WAIT => 2;
use constant MAX_ATTEMPTS => 10;
our $attempt = 0;

my $pid = undef;

while (not defined ($pid = fork())) {
    die "Too many failed fork() attempts: $!\n"
        if ++$attempt > MAX_ATTEMPTS;
    warn "fork() failed: $!\n";
    sleep $FORK_WAIT;
}

if ($pid) {

# I'm the father

} else {

# I'm the son

}