After spending what felt like a long time browsing through the documentation and so on I think I figured this out on my own, but now the time has come to ask for some enlightenment...

I am trying to write a subroutine that will accept either a filename to be opened and read from, or an already opened filehandle to just read from. My problem at first seemed to be that I had a poor understanding of what filehandles really were; but now after reading up on symbol tables I think I have that part fairly clear. What I am wondering is if there is a much better way to do this... or maybe there is already a module that does this, but I couldn't find one. Here is what I have come up with so far: 

# I am running with perl -w && strict BTW
sub read_file_or_handle {

    my $file_or_handle = shift;
    chomp $file_or_handle;

    unless(open FH, $file_or_handle )
    {
    no strict q(refs);
    *FH = *file_or_handle;
    }

    while (<FH>) {
       ...
    }
    close FH;  # closes it no matter what is was, right?
     
    # return something I read
}

[download]

One thing I don't like about this right away is that I am assuming I have an open filehandle based on the failed call to open. I'm used to more of an "open or die" construct, so I know that I'm opening my self up to trouble right there. Suggestions?

In reply to test if a scalar contains a filename or a filehandle? by mull

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