Objective: Create a perl daemon which will check a folder for the presence of a file, then move it to another folder based on extension. Extensions in use are .mp3, .wav, .txt.

I kludged together this script:

#!/usr/bin/perl


# Scripts to monitor Enco xfer folder and move the files to
# the proper folders on the Enco side.
#
# I hope!
#
# by Michael Barnes
#
#

use File::Copy;
use POSIX qw(setsid);

chdir '/' or die "Can't chdir to /: $!";
umask 0;
# next 4 lines commented for debugging
# open STDIN, '/dev/null' or die "Can't read /dev/null: $!";
# open STDOUT, '>/dev/null' or die "Can't write to /dev/null: $!";
# open STDERR, '>/dev/null' or die "Can't write to /dev/null: $!";
# defined(my $pid = fork) or die "Can't fork: $!";
unless(my $pid = fork()) {
exit if $pid;
setsid or die "Can't start a new session: $!";

while(1) {
sleep(5);
print "Hello...\n"; # for debugging
undef (@filelist); # attempt to clear array

@filelist = glob "/mnt/xfer/Enco/xfer/*";
@logs = grep (/txt|TXT/, @filelist); # cull out text files
@mp3 = grep (/mp3|MP3/, @filelist); # cull out mp3 files
@wav = grep (/wav|WAV/, @filelist); # cull out wav files

foreach $_ (@logs) {
push @logfile,$_;
}

foreach $logfile (@logfile) {
$newlogfile = $logfile;
$newlogfile =~ s/\/mnt\/xfer\/Enco\/xfer/\/tmp\/Data\/logs/;
print "'$logfile' and '$newlogfile'\n"; #for debugging
move ($logfile, $newlogfile) or die "Holy moly we got us a log error here hoss!";

}
$logfile = (); # attempt to clear array
undef ($newlogfile); # attempt to clear array

# Following segments for other file types are identical. Deleted for brevity in debugging.
}
}


Problem: Once started, the script runs fine. When some files are placed in the xfer folder they are properly moved to the correct folder and gone from the xfer folder. However, when the script loops through again, it tries to move the files again and crashes on the move since the files are gone.

Thoughts: It seems to me that the arrays are not clearing and are being re-read.

Ideas on fixing this are appreciated.

Thanks

----------------------------------------------------

In the above piece of code, you are setting the scalar $logfile to () and not the array @logfile
i guess that's the problem, just change the variable name or set @logfile to () and see.

ps: I don't have access to a linux system so could not check it myself.

I've had an issue trying to undef an array - might have been the way I was testing.
I use @array = "";

There are probably "better" answer(s).

Give that man a Kewpie doll!! That was it. A simple change from $ to @ and all works well.

Thanks!

That's why i never use the same (or too similar) names for scalars and arrays.
Also, the way to clear an array is
@arr = ();

you should do this for all the arrays at the top of the loop, just before (or just after) the sleep().
This block is redundant, you've already got an array of logfiles:

foreach $_ (@logs) {
push @logfile,$_;
}

Personally I always use proper names for loop vars, even if $_ is avail, it's just easier to read/debug, especially as progs get longer/more complex.

Always use

#!/usr/bin/perl -w
use strict;

at the top of your progs.
you can do a test compile/syntax check with
perl -wc yourprog.pl
which will check but not run it.

HTH

Apparently the OP uses common code in the loop for all 3 types.
Yes it might be avoided, but everybody has to develop their own style.

Well, he's got a generic list of all files: @filelist, then he greps out a sub-list for each type of file; @logs, @wav, @mp3 for processing.
Why copy each sub-list again?
BTW, a simpler way is
@arr1 = @arr2;

also, your greps are wrong,

e.g. you could have a file named txtwav.mp3

maybe better (with case-insensitive modifier 'i')

it's better to get the habit of using a block for map and grep too, as it keeps
your $_ local when you use it. Otherwise if you do a map with a s/// you might clobber
what you don't mean to.

always localise your $_ in a sub too.

maybe also a block will be compiled once only.

Filename parsing:

use File::Basename;

$base = basename($path);
$dir = dirname($path);
($base, $dir, $ext) = fileparse($path);