#! /usr/local/bin/perl

use Oraperl;
use DBI;
use FileHandle;
use rf;
use IO::Socket;
use IO::Handle;;
use POSIX qw(setsid);

open STDIN, '>/dev/null'   or die "Can't read /dev/null: $!";
print "Step 1\n";
#open STDOUT, '>','/dev/null' or die "Can't write to $prout: $!";
open(STDOUT, '>','/dev/null') or die "Can't write to $prout: $!";
print "Step 2\n";
open STDERR, '>/dev/null' or die "Can't write to $prerr: $!";
#SIG{CHLD} = 'IGNORE';
defined(my $pid = fork)   or die "Can't fork: $!";
exit if $pid;
setsid                    or die "Can't start a new session: $!";
#$SIG{CHLD} = 'DEFAULT';
#---------------------------
# Get Environment Variables
#---------------------------
$logdir = $ENV{out};
$constr = $ENV{CAAO_CSTR};
$user = $ENV{CAAO_USU};
$pass = $ENV{CAAO_PWD};
print"RUN\n";
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If you reopen STDOUT to /dev/null, where do you expect the output of print to go?

This line

open(STDOUT, '>','/dev/null') or die "Can't write to $prout: $!";
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redirects STDOUT to /dev/null therefore all 'print' is redirected into /dev/null.

If stepping through the program in Perl debugger doesn't help, try opening STDOUT/STDERR to some log file ("/tmp/$$.log", for example) or writing a __DIE__ signal handler:

sub {
 return unless defined $^S; # bail out if it's a parser error
 open my $log, ">/tmp/crash@{[time]}_$$.log";
 print $log @_;
}
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