internal: silence compiler warnings about unused return values (#13997)

* misc: silence warnings about ignoring return value on reads

silence warnings on ignored return values on read() and print an error
if it occurs.

* misc: silence warnings about ignoring return value on writes

silence warnings on ignored return values on write() and print an error
where we can, or pass them the maybe_unused attribute.

* misc: silence warnings about ignoring return value on pipe

silence warnings on ignored return value on pipe(), print an error and
exit on failure.

0 files changed, 0 insertions, 0 deletions