When you call a sub with parameters, those parameters arrive at the sub in the special array, @_. The usual practice is to copy the elements of that array immediately upon entering the sub.

sub foo {
   my ( $x, $y ) = @_;
   # ...
}
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Sometimes that's done this way:

sub foo {
    my $x = shift;
    my $y = shift;
    # ...
}
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In that case, rather than just copying, shift is actually pulling items off the array (which are then copied).

In each of these, you can call foo( 'hello', 'world' ), and $x will take the value 'hello' while $y takes the value 'world'. If you call foo( $howdy, $doody ), the variables $howdy and $doody won't be visible inside foo, but their values will be in $x and $y.

In your particular case, you're trying to print $removeq immediately upon entering the sub without grabbing the arguments first. The cleanthefile sub doesn't see the $removeq of the caller directly. It just gets a copy via the @_ array. (The fact that it doesn't have a variable by that name is what the "Global symbol "$removeq" requires explicit package name" error is about.)

It actually does take a copy later, on this line:

        my ( $sourcefile, $removeq )= @_;
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...but you're trying to print before that.

What I'd recommend, to start, is to get rid of that line, and put this at the very start of the sub:

my ( $removeq ) = @_;
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At that point, I think the problem you may have is that $sourcefile doesn't have a value. I don't see where that value might come from, so I don't know how to advise you on how to fix that.

If you're interested in the gory details of sub calls in Perl, see perlsub.

Call to sub-routine


my $removeq = $remove;
        my $sourcefile = "/u/ccsys/CC_print.printers";
        my $tempfile = "/u/ccsys/CC_print.printers.bkp_mkpq";
        &cleanthefile( $removeq, $sourcefile, $tempfile );
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sub cleanthefile {
    my @filehandles;
    my ( $sourcefile, $removeq, $tempfile ) = @filehandles;

    # Keep a dedicated backup of CC_print.printers
    if (-e "/root/CC_print.printers.bkp" ) {
        `cp -R $filehandles[1] $filehandles[2]`;
# create a temporary file
        if (-T ne "$filehandles[2]") {
        system("touch /u/ccsys/CC_print.printers.tmp");
        }

      # extract lines from $sourcefile which do NOT have the string to
+ remove
      # note that the \' inserts ticks so that strings with spaces can
+ work, too
        if ( -T "$filehandles[2]") {
        # system ("cat $sourcefile \| grep -v $removeq $sourcefile > $
+tempfile");
        `grep -v $filehandles[0] $filehandles[1] /dev/null /dev/null >
+ $filehandles[2]`;
        sleep 1;
        print "Waiting to unlink..\n";

        # delete source file, then rename working file
        unlink($filehandles[1]);
        rename( $filehandles[2], $filehandles[1] );
        system("rm -rf $filehandles[2]");

    }
}
    else {
        system("touch /u/ccsys/CC_print.printers.bkp");
        system("cp -R $filehandles[1] /root/CC_print.printer.bkp");
        print "Please re-run the program, had to create a backup\n";

    }
}
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I think you've got me on the right path Kyle, I can actually print the array of elements "@filehandles". It comes out in a order queuename, sourcefile, tempfile. Thanks so much for the help!