I'm writing a script that has to read from a binary file. Sometimes it has to read 1 byte, sometimes 4, sometimes 12. This seems ripe for a function, so I wrote one:

sub ReadBytes {
    my $num = shift;
    return undef if $num < 1;
    my @bytes;
    for (1..$num) {
        my $byte;
        read(BINFILE, $byte, 1);
        push @bytes, unpack("C",$byte);
    }
    return @bytes;
}

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The problem I have is that while I will always be reading from BINFILE in *this* script, this sub isn't very flexible and doesn't lend itself to code re-use (and therefore offends my sense of aesthetics). Further, since BINFILE is opened within another sub (ParseData, which does interesting things to the bytes I'm reading from BINFILE), I have ReadBytes embedded in ParseData. Nested subs are icky, in my book (there's that darned sense of aesthetics again), and there must be a better way to do it.

So my question is this: Just what is the Better Way To Do It?

Update: Passing the filehandle is just what I was looking for. For some reason I thought I'd have to tie it in some way - I forgot about passing a ref to the typeglob. Thanks all for your help!

"One word of warning: if you meet a bunch of Perl programmers on the bus or something, don't look them in the eye. They've been known to try to convert the young into Perl monks." - Frank Willison

In reply to Nested subs - inherently evil? by myocom

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