I recently had several instances where I had to try and figure out who holds what end of a unix pipe. To make this operation a bit more streamlined I created a small script to follow a pipe. I think it will be useful for other people debugging VDSM especially bugs related to "out of process" helpers not closing FDs properly.
To see all the exists of a pipe just input a known end of the pipe: stahlband <PID> <FD>
$ stahlband 5758 5 PID: 5758 FD: 5 KIND: r PID: 5758 FD: 6 KIND: w PID: 5770 FD: 5 KIND: r PID: 5770 FD: 6 KIND: w
The code is available on github: https://github.com/ficoos/stahlband
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