The original title was "apache2 and system", # 394424.
 
I'm trying to write a page that starts and stops a daemon. The symptom is that apache goes away and never comes back. Further actions on the page leave defunct processes in ps -ef (the called program or parent).
 
The original post was spot on for what I needed, so I tried it with different sleep times as the process to run.
 
The code is below. The amount of time ($tdiff) is always very low (about 0.004), however, the time apache "goes away" is directly proportional to the amount of time I set the sleep interval for (1, 10, 100).
 
It looks like perl finishes quickly, but apache does not return the page until all child processes finish, even if the perl process has.
 
Any advice on what to do to get the page back immediately? 
#!/usr/bin/perl

use strict;
use Time::HiRes qw (usleep time gettimeofday);
use CGI qw/:standard *table start_ul use_named_parameters/;     # load
+ standard CGI routines
use CGI::Carp qw /fatalsToBrowser/;

print "Content-Type:text/html\r\n\r\n";
print "<HTML>\n";
print "<HEAD></HEAD>\n";
print "<BODY>\n";
print "<CENTER>\n";
my $sleep = 100;
my $t1 = time;
print "using sleep of $sleep<BR>\n";
print "start time $t1<BR>\n";

# this was taken from the 2004 example vvvvvvvvvvvvvv
my $pid = fork;
die "Error forking: $!" unless defined $pid;
if (!$pid) {
    my $pid = fork;
    die "Error forking: $!" unless defined $pid;
    if (!$pid) {
        exec("sleep $sleep &");  # << except for this, changed from "f
+oo"
    }
    else {
        CORE::exit;
    }
}
# ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

my $t2 = time;
my $tdiff = $t2 - $t1;
print "end time $t2<BR>\n";
print "difference = $tdiff<BR>\n";
print "</CENTER>\n";
print "</BODY>\n";

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In reply to apache2 and system ... cotinued from 2004 by holandes777

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