use strict;
use warnings;
use File::Spec;
..

my @prog_dirs; # directory to find the program, still empty

if ($^O eq 'MSWin32'){
   @prog_dirs = qw(c: Programs devOps tools logs)
} 
elsif $^O eq 'Linux'){
   @prog_dirs = qw( opt devOps tools logs)
} 
else{...}

my $sqlLog = File::Spec->catfile( @prog_dirs, 'squirrel-sql-'.$creationTime.'.log');