Hello,

I am experiencing 2 problems with Perl 5.8 under mod_perl2 (apache 2) on Linux (Mandrake 9.1). Included is the subroutine and some example code to use it that can be used to replicate the problems.

Problem 1: When the program below is run, the program spits out "ERROR Bad file descriptor". There is no good reason for this. If I run the same code in the debugger it works correctly. I don't get it, I think this is a bug.

Problem 2: The subroutine below was written for a mod_perl module. When I make many connections to the server that causes this module to be run (subsequently executing the subroutine below) Apache's error_log contains many lines "ERROR Interrupted system call". By adding some debugging statements, I have discovered that this happens a few thousand times before stopping and uses up most/all of the cpu on the machine. What could be the cause of this? From the manpage I see EINTR is caused by an un-handled signal. Is there a way to tell what signal is causing this or where it came from?

Thanks for any help!

rr 

#!/usr/bin/perl -w

use strict;
use Symbol;
use Fcntl    qw(:DEFAULT);
use Socket;

use Time::HiRes;

print STDOUT simple("localhost", 80, "GET / HTTP/1.1\012Host:bidtxt.wh
+enu.com\012\012");

exit 0;

sub simple {
    my $host = shift || return undef;
    my $port = shift || return undef;
    my $mesg = shift || return undef;
    my $timeout = shift || 60;
    my $t0 = Time::HiRes::time(); my $ti;
    my $proto = getprotobyname('tcp'); 
    my $iaddr = inet_aton($host) || return undef;
    my $paddr = sockaddr_in($port, $iaddr);
    my $s = Symbol::gensym;
    socket($s, PF_INET, SOCK_STREAM, $proto) || return undef;
    connect($s, $paddr) || return undef;
    my $fd = fileno($s);
    my $t; my $b; my $res; my $nf; my $tl;
    my $buf = "\000" x 8120; ## BUFSIZ
    my $l = length($mesg);
    my $rin = 0 ; my $win = 0 , my $ein = 0; my $rout = 0; my $wout = 
+0; my $eout = 0;
    vec($rin, $fd, 1) = 1;
    vec($win, $fd, 1) = 1;
    $ein = $rin | $win;
    my $i;
    $t = 0; $b = 0;
    while (($nf, $tl) = select(undef, $wout=$win, $eout=$ein, 2)) {
        $i++;
        $ti = Time::HiRes::time() - $t0;
        if ($ti > $timeout) {
            print STDERR "Timed out writing ($ti) $!\n";
            shutdown($s, 2);
            return undef;
        }
        if (vec($wout, $fd, 1) == 1) {
            $b = syswrite($s, $mesg, $l - $b, $b);
            $t = $t + $b;
            last if $t = $l;
        }
        if (vec($eout, $fd, 1) == 1) {
            print STDERR "Got an error while writing: $!\n";
            shutdown($s, 2);
            return undef;
        }
    }
    $t = 0; $l = 0; $b = 0;
    while (($nf, $tl) = select($rout=$rin, undef, $eout=$ein, 2)) {
        $i++;
        $ti = Time::HiRes::time() - $t0;
        if ($!) { 
            print STDERR "ERROR $!\n";
        }
        if ($ti > $timeout) {
            print STDERR "Timed out reading ($ti) $!\n";
            shutdown($s, 2);
            return undef;
        }
        if (vec($rout, $fd, 1) == 1) {
            $b = sysread($s, $buf, 8192);
            $t = $t + $b;
            last if $b == 0;
            $res .= $buf;
        }
        if (vec($eout, $fd, 1) == 1) {
            print STDERR "Got an error while reading: $!\n";
            shutdown($s, 2);
            return undef;
        }
    }
    shutdown($s, 2);
    return $res;
}

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In reply to 2 problems using sockets perl 5.8 and mod_perl2 on Linux by rr

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