08-07-2008
Detecting if command is waiting for input
Hi,
After doing a fork and executing a shell, we execute (third party) commands which are essentially non-interactive. But some of them ask for input, under some (unforeseeable) circumstances. When this happens we go on waiting for output. Their is timeout, of course, but we don't seem to know if the process is actually doing some processing or is just simply waiting on us. Just wanted to ask if it is possible by some trickstery to find is the command is waiting for input. Note we can't parse the command output to check if it is waiting on input, because it varies across commands and becomes unmaintainable.
One possible approach that I can think of is looking out if the process is waiting on the stdin file descriptor. Could somebody elaborate as to how do I proceed in this direction.
thanks!
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