Interesting stuff, if painfully low level. However, characteristics of individual ioctl calls are device-dependent, and that FAQ mentions lower down:

FIONREAD requires a filehandle connected to a stream, meaning that sockets, pipes, and tty devices work, but not files.

Since I am reading plain files, that isn't going to work for me.

Hugo

In reply to Re: Re: nonblocking I/O - testing whether file has more data to read by hv
in thread nonblocking I/O - testing whether file has more data to read by hv

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