Check if piped-in process is blocked on input

Suppose I am the author of a shell utility called bar. One common use case is in pipelines like foo | bar, where foo sometimes runs interactively. I want to distinguish situations where interaction is required from situations where foo produces all its output up front and immediately exits.

Is it possible from within bar to determine a) the process that's piping into it; b) whether that process is blocked on input? If it's possible, what system calls do I need?

is a duplicate

This question has been asked before and has already been answered. It should be marked as a duplicate.

Please enter the URL of the proposed duplicate in the details field below.

not constructive

This question cannot be answered in a way that is helpful to anyone. It's not possible to learn something from possible answers, except for the solution for the specific problem of the asker.

Communities

Check if piped-in process is blocked on input

0 comment threads

0 answers