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POCan't read from socket in perl - possible deadlock?
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copied!<p>My OS is Archlinux with perl 5.14.2. I am just trying to write a little program to accomplish a remote comlile. The program just passes a C source file to the server. The server will call gcc to compile the C code and pass the compiler's message. The client can't receive the compiler's message. I have the message in the server. There is the code:</p> <pre><code>#!/usr/bin/perl -w # oj.pl --- alpha use warnings; use strict; use IO::File; use IO::Socket; use constant MY_TRAN_PORT => 138000; $| = 1; my $tmpFileToBeCompiled = IO::File->new ("> tmpFile09090989.c") or die "Can't creat this file"; #if (defined $tmpFileToBeCompiled) { # print $tmpFileToBeCompiled "argh"; # just for test! #} # $fihi->close; my $port = shift || MY_TRAN_PORT; my $sock_server = IO::Socket::INET->new (Listen => 20, LocalPort => $port, Timeout => 60, Reuse => 1) or die "Can't create listening socket: $!\n"; my $tmp = 1; while ($tmp) { next unless my $session = $sock_server->accept; my $peer = gethostbyaddr ($session->peeraddr, AF_INET) || $session->peerhost; warn "Connection from [$peer, $port]\n"; while (<$session>) { print $tmpFileToBeCompiled $_; # if it works, the filehandle should be changed into tmpFile. just fixed. print $session "test!"; } my @lines = `gcc tmpFile09090989.c 2>&1`; foreach ( @lines) { print $session $_ . "test!!!\n"; # $session->print; } print "OK!"; $tmpFileToBeCompiled->close; warn "Connecting finished!\n"; $session->close; $tmp --; } $sock_server->close; ----------------------------------------end-------------------------------------------------------- -------------------------------------client.pl-------------------------------------------------------- use warnings; use strict; use IO::Socket qw(:DEFAULT); use File::Copy; use constant MY_TRAN_PORT => 138000; use IO::File; my $host = shift || '127.0.0.1'; my $port = shift || MY_TRAN_PORT; my $socket = IO::Socket::INET->new("$host:$port") or die $@; my $fh = IO::File->new("a.c", "r"); my $child = fork(); die "Can't fork: $!\n" unless defined $child; # if (!$child) { # $SIG{CHLD} = sub { exit 0 }; # userToHost(); # print "Run userToHost done!\n"; # $socket->shutdown(1); # sleep; # } else { # hostToUser(); # print "Run hostToUser done! \n"; # warn "Connection closed by foreign host\n"; # } userToHost(); unless ($child) { hostToUser(); print "Run hostToUser done! \n"; warn "Connection closed by foreign host\n"; $socket->close; } sub userToHost { while (<$fh>) { # print $_; # for debug print $socket $_; } } sub hostToUser { while (<$socket >) { print $_; } } # copy ("a.c", $socket) or die "Copy failed: $!"; print "Done!"; </code></pre>

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