If your intentions were to do something, then you should have mentioned that in your original post. If you intended to speak to the general case, then you should be talking about pipes, not system. But this statement that you made: "Some commands are built as ffpmpeg specifically is, but a great many are not." This just seems, generally speaking, misleading.

Virtually all (if not all) commands take in STDIN and emit STDOUT and STDERR. Some programs do not need to use these standard streams, but that is beside the point: for this thread ... piping in-memory data to another program via its STDIN is the general case.

jeffa

L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
B--B--B--B--B--B--B--B--
H---H---H---H---H---H---
(the triplet paradiddle with high-hat)

In reply to Re^4: Passing an in memory scalar to an external command as an argument by jeffa
in thread Passing an in memory scalar to an external command as an argument by Rodster001

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