perl多進程主進程等子進程結束

將“use POSIX ":sys_wait_h";”去掉，還有在主進程中列印子進程中的變數是不對的，主進程不知道子進程的狀況，除非你用pipe將變數值傳給主進程，###################################################!/usr/bin/perl#use POSIX ":sys_wait_h";my $a=10;for($i=1;$i<=3;$i++){my $pid=fork();  if (!defined($pid)) {        print "Error in fork: $!";        exit 1;    }   if ($pid == 0 ) {        if($i==1){        sleep(9);        $b1=$a+1;        print "$b1\t";        exit 0;}        elsif($i==2){        sleep(5);        $b2=$a+10;        print "$b2\t";        exit 0;}        else{        sleep(3);        $b3=$a+100;        print "$b3\t";        exit 0; }}}print "~~~~~~~~~~split~~~~~~~~~~~\n";while (($collect = waitpid(-1, WNOHANG)) > 0) {            1;}##################### 輸出 ##########bsd2# perl test.pl~~~~~~~~~~split~~~~~~~~~~~110     20      11      bsd2#