Why not simply pass the filename of the file-to-be-written to the program, and let it do the file writing in any case?

On Linux, the -p file test can tell you if STDOUT is connected to a pipe, no idea if that works on windows too (Update: -t is probably more informative than -p).

Perl 6 - links to (nearly) everything that is Perl 6.

In reply to Re: Test whether STDOUT is connected to a file by moritz
in thread Test whether STDOUT is connected to a file by rovf

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