To: Chester Ramey <chet.ra...@case.edu> On thu., dec. 19 of 2019 at 12:40, Chet Ramey (<chet.ra...@case.edu>) wrote:
> On 12/18/19 6:40 PM, Bize Ma wrote: > > >>> The exit status is 0 if input is available on the specified file > > descriptor, non-zero otherwise. > > Bash-5.0 uses select/FIONREAD to determine whether or not there is input > available on the file descriptor. Those don't wait; they test whether or > not there is input on the specified file descriptor at the point they are > called. > Thanks Chet. Could you please comment about this assertions: 1.- bash will either do a select() or an ioctl(FIONREAD), or neither of them, but not both, as it should for it to work. read -t0 is broken. Do not use it – mosvy. <https://unix.stackexchange.com/questions/33049/how-to-check-if-a-pipe-is-empty-and-run-a-command-on-the-data-if-it-isnt/498064#comment969997_498064> 2.- Conclusion: read -t0 is *broken* in bash. Don't use it. – <https://unix.stackexchange.com/users/308316/mosvy> mosvy <https://unix.stackexchange.com/questions/33049/how-to-check-if-a-pipe-is-empty-and-run-a-command-on-the-data-if-it-isnt/498065?noredirect=1#comment916652_497121>
