File not being written to and no errors?

I have a file I am trying to read and write to, it's obviously opening
it ie.. No errors but not writing to it.

Since no errors are being produced I can't figure out why? 

In short I am reading the file to see if I previously sent an email
concerning a "name" and if I have then don't send another email, if I
have not then do send an email. 

I am pretty sure of the logic as I receive the email, but it is not
writing the new "name" to the file.

 

Above and below, I am opening another file read/write in the same way
and it works just fine. Any suggestions on how to check what's going on?
I am using strict, warnings and diagnostics and everything appears to be
clear.

 

File:

-rwxrwxrwx    1 root     root           11 Jul 28 08:59 sent

 

1)

#!/usr/bin/perl

use strict;

use warnings;

use diagnostics;

use Net::NBName;

use Fcntl ':flock';

use Net::Ping::External qw(ping);

our ($d,$m,$y)=(localtime(time-86400))[3..5];$m+=1;$y+=1900;

...

...

2)

our $done='/var/scripts/snmp/sent';

our %sent=();

...

...

3)

open (DONE,"+>>$done") or die "Cannot open file: $!";

flock (DONE, 1);

foreach (<DONE> ){

chomp($_);

$sent{$_}="";

}

....

...

if (exists $sent{$mapn}){

}else{

...

...

4)

}elsif($ns && ($ns->as_string =~ /^(.*)\s*\<00\>/i)) {

push @mailbody, "AN
UNAUTHORIZED Device Was Detected\n";

push @mailbody,
"$maprh,$maprb,$maprp,$maprm,$mapip,$1\n";

print DONE "$1\n";

 

...

...

5)

...

flock(DONE, 8);

close(DONE);

...

 

 

 

Thanks,

Rich

 

On Jul 29, arichmond(contr-ird) said:

>I have a file I am trying to read and write to, it's obviously opening
>it ie.. No errors but not writing to it.
>
> Since no errors are being produced I can't figure out why?

You are opening a file for appending and reading.  But you forgot (or
didn't know) that you start out at the *end* of the file.

>open (DONE,"+>>$done") or die "Cannot open file: $!";
>
>        flock (DONE, 1);

You should really be using Fnctl.pm's file locking constants instead of
numbers here.

Anyway, here is where you should say:

s DONE, 0, 0;

to rewind to the beginning of the file.

>        foreach (<DONE> ){

Don't do that.  Use a while loop instead, PLEASE.

--
Jeff "japhy" Pinyan         %  How can we ever be the sold short or
RPI Acacia Brother #734     %  the cheated, we who for every service
http://japhy.perlmonk.org/  %  have long ago been overpaid?
http://www.perlmonks.org/   %    -- Meister Eckhart

On Jul 29, japhy@perlmonk.org said:
 

I didn't thanks for the tip

>open (DONE,"+>>$done") or die "Cannot open file: $!";
>
>        flock (DONE, 1); 

Thanks, I read the perldocs and all the referring docs and understand
now what I am really trying to do
 

Fixed this and all the others throughout my script and it works
beautifully now, thanks for the help.