Perl Pipe不重定向Java进程输出

Question

我试图控制游戏服务器并实时显示其输出。 这是我到目前为止的内容：

#!/usr/bin/perl -w
 use IO::Socket;
 use Net::hostent;              # for OO version of gethostbyaddr

 $PORT = 9000;                  # pick something not in use

 $server = IO::Socket::INET->new( Proto     => 'tcp',
                                  LocalPort => $PORT,
                                  Listen    => SOMAXCONN,
                                  Reuse     => 1);

 die "can't setup server" unless $server;
 print "[Server $0 accepting clients]\n";

 while ($client = $server->accept()) {
   $client->autoflush(1);
   print $client "Welcome to $0; type help for command list.\n";
   $hostinfo = gethostbyaddr($client->peeraddr);
   printf "[Connect from %s]\n", $hostinfo->name || $client->peerhost;
   print $client "Command? ";

   while ( <$client>) {
     next unless /\S/;       # blank line
     if    (/quit|exit/i) {
        last;                                     }
     elsif (/fail|omg/i) {
        printf $client "%s\n", scalar localtime;  }
     elsif (/start/i ) {
        if (my $ping_pid = open(JAVA, "screen java -jar craftbukkit-0.0.1-SNAPSHOT.jar |")) {
    while (my $ping_output = <JAVA>) {
        # Do something with the output, let's say print
        print $client $ping_output;

        # Kill the C program based on some arbitrary condition (in this case
        # the output of the program itself).
                }
        }
        printf $client "I think it started...\n Say status for output\n";                }
     elsif (/stop/i ) {
        print RSPS "stop";

    close(RSPS);
        print  $client "Should be closed.\n"; }
     elsif (/status/i ) {
        $output = RSPS;
        print $client $output;      }
     else {
       print $client "FAIL\n";
     }
   } continue {
      print $client "Command? ";
   }
   close $client;
 }

它可以很好地启动进程，唯一的缺陷是它没有将Java进程的输出输出到套接字（它是在Perl初始化时在终端窗口中显示输出的），我用ping尝试了一下，并且工作了很好，有什么想法吗？

提前致谢！

Answer 1

听起来Java代码（或者也许是screen ）正在将一些输出打印到标准错误流中。 假设您不想单独捕获它 ，则一些简单的修复方法是：

抑制它：

open(JAVA, "screen java -jar craftbukkit-0.0.1-SNAPSHOT.jar 2>/dev/null |")

在标准输出流中捕获它：

open(JAVA, "screen java -jar craftbukkit-0.0.1-SNAPSHOT.jar 2>&1 |")

Answer 2

screen将输出重定向到“屏幕”。 摆脱命令中的screen 。