perl - Get the value of a process executed in a child back to parent -

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i'm looking solution allows me return values of process executed in child parent process. try have no idea hook return value: 

use proc::processtable; use posix qw(:signal_h :errno_h :sys_wait_h); $sig{chld} = \&reaper;  $count (1..10) {  # start few demo childs  if (fork () == 0) {   &startchild;   exit 0;  }      }   {  print "working\n";  sleep 1; } while (chkchildprocess());  sub startchild {   print "starting child $$\n";   system("date"); #==>need output of "date" parent   sleep 2 + rand 7;    print "end  child $$\n"; }  sub chkchildprocess {  $p (@{new proc::processtable->table}){   if ($p->ppid == $$){    $curpid{$$}=$p->pid;    return 1;   }  }  return undef; }   sub reaper { $pid; $pid = waitpid(-1, &wnohang); if ($pid == -1) {  # no child waiting.  ignore it. } elsif (wifexited($?)) {  print "process $pid exited.\n"; } else {  print "false alarm on $pid.\n"; } $sig{chld} = \&reaper;          # in case of unreliable signals }

any great.

the bg_eval , bg_qx methods of forks::super made solve problem.

use forks::super 'bg_eval';  @result; $count (1 .. 10) {      $result[$count] = bg_eval {         $date = `date`;         sleep 2 + rand 7;         return $date;     }; }  print "$result[$_]\n" 1..10;

the block after bg_eval run asynchronously in background process. when background process finished, variable $result[$count] populated result.

when print $result[$_], 1 of 2 things happen. if background process associated variable finished, contain return value. if background process not finished, wait process finish, , make return value available in value.


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