多线程ping

zllfdd

ping.pl

1. 
   
2. #!/usr/bin/perl -w
   
3. use strict;
   
4. use Net::Ping;
   
5. use threads;
   
6. use threads::shared;
   
7. 
   
8. my @host = split(/\./,$ARGV[0]);
   
9. $SIG{ALRM} = sub {print "time out\n"};   #不加这个会出现Alarm clock，加上了没反应
   
10. my $next:shared = 1;                       #说明$next是个共享的变量，似乎必须要加
    
11. sub my_ping(){
    
12.     my @ip = @host;
    
13.     my $p = Net::Ping->new();
    
14. 
    
15.     {lock $next;$ip[3]=$next;$next++};    #对$next加锁
    
16.     while($ip[3] <= 254){
    
17.         my $remote_ip = join(".",@ip);
    
18.         #print "$remote_ip\n";
    
19.         print "$remote_ip is alive.\n" if $p->ping($remote_ip);
    
20.         {lock $next;$next++;$ip[3]=$next};
    
21.         sleep(1);
    
22.     }
    
23. 
    
24.     $p->close();
    
25. }
    
26. my $max_thread = 10;
    
27. my @t;
    
28. while($max_thread-- > 0){
    
29.     push @t,threads->new(\&my_ping);        #创建新线程
    
30. }
    
31. for(@t){
    
32.     print "..\n";                                    #有线程退出了
    
33.     $_->join;
    
34. }
    

复制代码

用法：
./ping.pl 192.168.0.1
将依次的ping 192.168.0.1 ~ 192.168.0.254

搞了一下午，还是没明白 use Thread; 和 use threads;有什么区别，
不过总算是能用了，呵呵

helbreathszw

线程是有问题的
在centos3,centos4跑一下，就出来问题的！

helbreathszw

CLONE_THREAD
              (Linux 2.4 onwards) If CLONE_THREAD is set, the child  is  placed  in  the
              same thread group as the calling process.

              If  CLONE_THREAD  is  not  set,  then the child is placed in its own (new)
              thread group, whose ID is the same as the process ID.

              (Thread groups are feature added in Linux 2.4 to support the POSIX threads
              notion  of  a set of threads sharing a single PID.  In Linux 2.4, calls to
              getpid(2) return the thread group ID of the caller.)

zllfdd

谢谢楼上提醒，没想那么多。