Perl Script Not Liking Date Extension - perl

Question

why do I receive the error complaining about the parenthesis ?
sh: syntax error at line 1 : `)' unexpected
when adding this date extension to the new file -- mv abc abc$(date +%Y%m%d%H%M%S)
for it seems that it doesn't like that last parenthesis
#!/usr/bin/perl
# =========================================== #
# Script to watch POEDIACK file size
#
# - Comments -
#
# script will check the file size of the POEDIACK file in
# $LAWDIR/$PLINE/edi/in.
# If it's > 1 gig, it will send notification via email
#
#
# =========================================== #
use strict;
use POSIX qw(strftime);
# get env vars from system
my $LAWDIR = #ENV{'LAWDIR'};
my $PLINE = #ENV{'PLINE'};
#my $email_file = "/lsf10/monitors/poediack.email";
my $curr_date = strftime('%m%d%Y', localtime);
my $ack_file = "$LAWDIR" . "/$PLINE" . "/edi/in/POEDIACK";
my $ack_location = "$LAWDIR" . "/$PLINE" . "/edi/in/";
my $mv_location = "$LAWDIR" . "/$PLINE" . "/edi/in/Z_files";
my $ack_file_limit = 10;
#my $ack_file_limit = 1000000000;
my $ack_file_size;
if( -e $ack_file)
{
$ack_file_size = -s $ack_file;
if ( $ack_file_size > $ack_file_limit )
{
`compress -vf $ack_file`;
`mv $mv_location\$ack_file.Z $mv_location\$ack_file.Z.$(date +%Y%m%d%H%M%S)`;
}
}
else
{
print "POEDIACK File not found: $ack_file\n";
}
### end perl script ###

Answer 1

$( is being interpreted as a variable. It is the group ID of the process. You need to escape it.
And you probably shouldn't escape $ack_file.
`mv $mv_location$ack_file.Z $mv_location$ack_file.Z.\$(date +%Y%m%d%H%M%S)`;
It's safer and faster to avoid complicated shell commands and use rename instead.
use autodie;
my $timestamp = strftime('%Y%m%d%H%M%S', localtime);
rename "$mv_location$ack_file.Z", "$mv_location$ack_file.Z.$timestamp";
Or use an existing log rotator.