How to get PIDs connected to another PID's standard input/output/error?
After something like first_command | … | last_command & $! is set to the PID of last_command. How can I find the other PIDs in this pipeline? Especially, is there a convenient way to find the PID of the second to last command? I can look in /proc/$!/fd/0 and grep for the pipe number in ls /proc/*/fd/1, but that isn't exactly reliable.
bash background-process
asked 2 hours ago
l0b0l0b0
28.5k19121248
add a comment |
After something like first_command | … | last_command & $! is set to the PID of last_command. How can I find the other PIDs in this pipeline? Especially, is there a convenient way to find the PID of the second to last command? I can look in /proc/$!/fd/0 and grep for the pipe number in ls /proc/*/fd/1, but that isn't exactly reliable.
bash background-process
asked 2 hours ago
l0b0l0b0
28.5k19121248
Looks like it has been asked before.
– Weijun Zhou
59 mins ago
@WeijunZhou I had only read as far as the two first solutions, but the third looks like it would work without changing the commands, which was what I was looking for.
– l0b0
8 mins ago
add a comment |
After something like first_command | … | last_command & $! is set to the PID of last_command. How can I find the other PIDs in this pipeline? Especially, is there a convenient way to find the PID of the second to last command? I can look in /proc/$!/fd/0 and grep for the pipe number in ls /proc/*/fd/1, but that isn't exactly reliable.
bash background-process
asked 2 hours ago
l0b0l0b0
28.5k19121248
After something like first_command | … | last_command & $! is set to the PID of last_command. How can I find the other PIDs in this pipeline? Especially, is there a convenient way to find the PID of the second to last command? I can look in /proc/$!/fd/0 and grep for the pipe number in ls /proc/*/fd/1, but that isn't exactly reliable.
bash background-process
bash background-process
asked 2 hours ago
l0b0l0b0
28.5k19121248
asked 2 hours ago
l0b0l0b0
28.5k19121248
asked 2 hours ago
l0b0l0b0
28.5k19121248
asked 2 hours ago
l0b0l0b0
28.5k19121248
asked 2 hours ago
l0b0l0b0
28.5k19121248
28.5k19121248
Looks like it has been asked before.
– Weijun Zhou
59 mins ago
@WeijunZhou I had only read as far as the two first solutions, but the third looks like it would work without changing the commands, which was what I was looking for.
– l0b0
8 mins ago
add a comment |
Looks like it has been asked before.
– Weijun Zhou
59 mins ago
@WeijunZhou I had only read as far as the two first solutions, but the third looks like it would work without changing the commands, which was what I was looking for.
– l0b0
8 mins ago
Looks like it has been asked before.
– Weijun Zhou
59 mins ago
Looks like it has been asked before.
– Weijun Zhou
59 mins ago
@WeijunZhou I had only read as far as the two first solutions, but the third looks like it would work without changing the commands, which was what I was looking for.
– l0b0
8 mins ago
@WeijunZhou I had only read as far as the two first solutions, but the third looks like it would work without changing the commands, which was what I was looking for.
– l0b0
8 mins ago
add a comment |
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Looks like it has been asked before.
– Weijun Zhou
59 mins ago
@WeijunZhou I had only read as far as the two first solutions, but the third looks like it would work without changing the commands, which was what I was looking for.
– l0b0
8 mins ago