Hello talexb,

You are passing in $fh as a scalar, then overwriting it in the line $fh = Symbol::gensym;, so $fh works correctly inside Extra::open but remains undef in the caller. You need to pass in a reference, and dereference it accordingly within Extra::open:

{
    my $fh;
    Extra::open ( \$fh, '>', 'extra-open.txt' ) or
        die "2. Open failed: $!";
    defined $fh or die "2. Filehandle not defined";
    print $fh "Extra open works fine.\n";
    close ( $fh );
}

[download]
package Extra;

use Symbol;

sub open
{
    my ( $fh, $direction, $filename ) = @_;
    
    $$fh = Symbol::gensym;
    open ( $$fh, $direction, $filename );
}

1;

[download]

In my (minimal) testing, this writes the correct messages to the two output files, and no error is generated.

Hope that helps,

Athanasius <°(((>< contra mundum Iustus alius egestas vitae, eros Piratica,

In reply to Re: Looking for suitable spells to get open to return a filehandle from a module by Athanasius
in thread SOLVED: Looking for suitable spells to get open to return a filehandle from a module by talexb

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