Your $comb is not declared to satisfy strict, 

# . . .
    my $comb = $var_a . $var_b;

[download]
Then you try to use the value of $comb as the filehandle name as well as part of the file name. Why not use a lexical file handle? You open the file to read, not write, so your print will fail in any case. 
    open (my $fh, '>', "c:\\my\\dest\\dir\\" . $comb . "found.txt")
        || die "failure to create" . $comb;
    print $fh $var_c, "content detail for file found\n";

[download]

After Compline,
Zaxo

In reply to Re: How do you properly use a variable for FILEHANDLE in print vs open by Zaxo
in thread How do you properly use a variable for FILEHANDLE in print vs open by Anonymous Monk

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