求教：线程问题

Question

最近学习线程，编写测试程序manage.pl，利用线程访问srv.list中的服务器，取得uname -a 的值，但是提示
Thread 1 terminated abnormally: Not a CODE reference at manage.pl line 17.

另外如果列表中某台服务器不能访问，程序会中断
并提示
Permission denied at manage.pl line 35
Perl exited with active threads:
        0 running and unjoined
        6 finished and unjoined
        0 running and detached

1. #!/usr/bin/perl
2. use strict;
3. use Net::SSH::Perl;
4. use threads;
5. use Thread::Queue;
7. my $queue = new Thread::Queue;
8. my $max = 10;
10. open my $IN, '<', 'srv.list' or die "Don't open File!\n";
11. while (<$IN>)
12. {
13.    $queue->enqueue($_);
14. }
15. close $IN;
17. for ( my $n = 0; $n < $max; $n++)
18. {
19.     threads->create(\&exec_command());
20. }
22. foreach my $th (threads->list(threads::all))
23. {
24.         $th->detach();
25. }
27. sub exec_command()
28. {
29.    my $host = $queue->dequeue();
30.    my $user = 'zoomi';
31.    my $pass = 'zoomi-init';
32.    my $cmd='uname -a';
34.    my $ssh = Net::SSH::Perl->new($host);
35.    $ssh->login($user, $pass);
36.    my($stdout, $stderr, $exit) = $ssh->cmd($cmd);
38.    if ($exit == 0) {
39.       print "$host -> $stdout";
40.    } else {
41.       print "$host -> $stderr";
42.    }
43. }

复制代码

1. 10.60.30.15
2. -> Linux zoomi-30-15 2.6.31-14-generic #48-Ubuntu SMP Fri Oct 16 14:05:01 UTC 2009 x86_64 GNU/Linux
3. Thread 1 terminated abnormally: Not a CODE reference at manage.pl line 17.
4. 10.60.30.16
5. -> Linux zoomi-30-16 2.6.31-23-server #74-Ubuntu SMP Mon Feb 28 22:32:34 UTC 2011 x86_64 GNU/Linux
6. Thread 2 terminated abnormally: Not a CODE reference at manage.pl line 17.
7. 10.60.30.17
8. -> Linux zoomi-30-17 2.6.31-14-generic #48-Ubuntu SMP Fri Oct 16 14:05:01 UTC 2009 x86_64 GNU/Linux
9. Thread 3 terminated abnormally: Not a CODE reference at manage.pl line 17.
10. 10.60.30.18
11. -> Linux zoomi-30-18 2.6.31-14-server #48-Ubuntu SMP Fri Oct 16 15:07:34 UTC 2009 x86_64 GNU/Linux
12. Thread 4 terminated abnormally: Not a CODE reference at manage.pl line 17.
13. 10.60.30.19
14. -> Linux ubuntu 2.6.31-14-server #48-Ubuntu SMP Fri Oct 16 15:07:34 UTC 2009 x86_64 GNU/Linux
15. Thread 5 terminated abnormally: Not a CODE reference at manage.pl line 17.
16. 10.60.30.25
17. -> Linux zoomi-30-25 2.6.31-14-server #48-Ubuntu SMP Fri Oct 16 15:07:34 UTC 2009 x86_64 GNU/Linux
18. Thread 6 terminated abnormally: Not a CODE reference at manage.pl line 17.
19. 10.60.30.27
20. -> Linux server-A-test 2.6.31-14-server #48-Ubuntu SMP Fri Oct 16 15:07:34 UTC 2009 x86_64 GNU/Linux
21. Thread 7 terminated abnormally: Not a CODE reference at manage.pl line 17.
22. 10.60.30.28
23. -> Linux zoomi-30-28 2.6.31-14-generic #48-Ubuntu SMP Fri Oct 16 14:05:01 UTC 2009 x86_64 GNU/Linux
24. Thread 8 terminated abnormally: Not a CODE reference at manage.pl line 17.
25. 10.60.30.29
26. -> Linux server-B-test 2.6.31-14-server #48-Ubuntu SMP Fri Oct 16 15:07:34 UTC 2009 x86_64 GNU/Linux
27. Thread 9 terminated abnormally: Not a CODE reference at manage.pl line 17.

复制代码

Answer 1

本帖最后由 albertd 于 2011-04-15 02:31 编辑

1. sub exec_command()
2. {
3.    my $user = 'xxxxx';
4.    my $pass = 'xxxxx';
5.    my $cmd='uname -a';
7.    while (my $host = $queue->dequeue())
8.        {
9.            eval {my $ssh = Net::SSH::Perl->new($host);
10.                $ssh->login($user, $pass);
11.                my($stdout, $stderr, $exit) = $ssh->cmd($cmd);
13.                if ($exit == 0) {
14.                print "$host -> $stdout";
15.                } else {
16.                print "$host -> $stderr";
17.                }
18.            };
19.         warn $@ if $@;
20.    }
21. }

复制代码Should fix the issues.

Answer 2

Should fix the issues.
albertd 发表于 2011-04-15 02:29

那个报错产生的原因是什么？还有我的程序运行后，不能正常退出 。

Answer 3

本帖最后由 ykredrum 于 2011-04-16 22:24 编辑

2. for ( my $n = 0; $n < $max; $n++)
4. {
6.     threads->create(\&exec_command());
8. }

复制代码\&exec_command()
似乎多了对括号吧

应该是 \&exec_command

Answer 4

对了
最好用个
Thread::Semaphore模块
控制一下线程，确保线程都完成了任务，主线程才退出
不然闪一下就没有了
模块里有具体例子

Answer 5

我现在也在学线程啊。