if (fork() == 0) {
 system("sh", "-c", "sleep 3 # getting yandex translation");
 exit(0);
}
if (fork() == 0) {
 system("sh", "-c", "sleep 2; # getting google translation");
 exit(0);
}

system("pstree -Apal $$"); # pstree gets the PID of the parent process as its argument

while((my $pid = wait()) != -1) {
 say "$pid terminated"
}
__END__
perl,29173 test.pl
  |-perl,29174 test.pl
  |   `-sh,29177 -c sleep 3 # getting yandex translation
  |       `-sleep,29179 3
  |-perl,29175 test.pl
  |   `-sh,29178 -c sleep 2; # getting google translation
  `-pstree,29176 -Apal 29173
29175 terminated
29174 terminated

##</code><code>##

my $start = time;

if (fork() == 0) {
 # arm the alarm clock
 alarm(10);
 # create a child process that sleeps
 system("sleep 365d");
 exit(0);
}

system("pstree -Apal $$");

while((my $pid = wait()) != -1) {
 say "$pid terminated"
}

say time-$start, " seconds elapsed instead of a year"
__END__
perl,29620
  |-perl,29621
  |   `-sleep,29623 365d
  `-pstree,29622 -Apal 29620
29621 terminated
10 seconds elapsed instead of a year