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by thatcks 3864 days ago
A note: SIGHUP is far from obsolete in its original purpose. We may have stopped using modems but people still log in to Unix machines in ways that can get disconnected. If you SSH in to a machine and your SSH session is cut off by a network issue, your shell (and any command you have running) will get a SIGHUP.
1 comments
dozzie 3864 days ago
There's more than that in SIGHUP. It's sent to the process group owning the terminal[1] (/dev/tty[1-X], /dev/pts/*) when said terminal is closed. Your shell, Midnight Commander, Vim, Emacs, and what not terminates when you close your terminal emulator window.

[1] I don't quite remember what happens to other process groups, since you could have some background jobs stopped.

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misterdata 3864 days ago
Yes, and using the 'nohup' utility you can effectively block the delivery of SIGHUP to a particular process, to ensure it does not terminate when you close your SSH connection.
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jon-wood 3864 days ago
Awesome, I knew nohup could be used for that, but hadn't worked out why it was called that.
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