#!/usr/bin/perl

my $pattern = "PGP";

&renameFiles('/home/user/perl/testincoming');

sub renameFiles {
	# Pass directory name as parameter
	my $Dir = shift;

	opendir(DIR, $Dir) || die "Can't opendir $Dir: $!";
	my @Files = grep { -f "$Dir/$_" } readdir(DIR);
	rewinddir(DIR);
	my @Dirs = grep { /^[^.].*/ && -d "$Dir/$_" && ! -l "$Dir/$_"} readdir(DIR);
	closedir DIR;

	foreach $file (@Files) {
		open(FILE,"<$Dir/$file") || die "Can't open $file: $!";
		my $doRename=0;
		READFILE: while (<FILE>) {
			if (/\Q$pattern\E/) {
				$doRename=1;
				last READFILE;
			}
		}	
		close(FILE);
                if ($doRename) {
			my $newname=$file;
                	$newname=~s/^./o/;
                	rename ("$Dir/$file", "$Dir/$newname");
		}
	}

	# Call self for each subdir	
	foreach $SubDir (@Dirs) { &renameFiles(join("/",$Dir,$SubDir)); }
};