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Actually the new top comment blew me away. I'm in the 20 year veteran category and was also oblivious. Quoted: disown - bash built in. You know how you always

Actually the new top comment blew me away. I'm in the 20 year veteran category and was also oblivious. Quoted: disown - bash built in. You know how you always start that mega long rsync in an ssh session from your laptop and then realize you have to go offline halfway through? You forgot to start it in screen or nohup, didn't you? You can pause it (ctrl+z), background it (bg), and then disown it so it is protected from SIGHUP when you quit your ssh session. Bash (and, to be fair, zsh and others have copied much of this) has some wonderful job control features most people are completely oblivious of - even veterans of 20 years.

sgt 15y ago
disown is great. However, I don't know if it's possible to start up a new shell, then bring back that process to the foreground. 'jobs' will return no entries, and fg doesn't take a PID parameter. Any ideas? It would be brilliant if that were possible with bash alone.
- pja 15y ago
  reptyr: https://github.com/nelhage/reptyr https://github.com/nelhage/reptyr is Linux specific & involves a fairly gruesome abuse of ptrace() to attach a running process to your current pty. It won't put the process in the shell jobs list though. There's also retty: http://pasky.or.cz/dev/retty/ http://pasky.or.cz/dev/retty/ but again it's not a complete solution.
- xyzzyb 15y ago
  disown -h will (reportedly) keep it under job control.
  - pja 15y ago
    True, but doesn't help if you've quit the shell & want to re-attach to the process after logging back in again :(
- tel 15y ago
  Screen is the only real answer, I've ever found.
  - gnosis 15y ago
    There's also 'tmux': http://tmux.sourceforge.net/ http://tmux.sourceforge.net/
    - tel 15y ago
      True, screen and screenlikes. I've never used tmux, mostly because screen just works well enough for me.
    - dredmorbius 15y ago
      Which according to reports has the benefit of being maintainable. GNU screen, which I love and use to obscene extents daily, has an exceptionally hairy codebase. That said, I've got to get my tmux on and learn how to do screen equivalents with it.... http://www.techrepublic.com/blog/opensource/is-tmux-the-gnu-screen-killer/1901 http://www.techrepublic.com/blog/opensource/is-tmux-the-gnu-...
      - res0nat0r 15y ago
        I keep seeing people comment on the codebase of screen being bad vs tmux, but I'm not sure why that is an issue? Are there any features of screen missing that haven't been added to the codebase? The vertical split patch has been added a long while back, and even though I'm sure tmux has a smaller memory footprint, I've never had an occasion where screen has ever been an app I'm worried might impact my server memory usage. Since it is installed for the most part everywhere I have no desire to switch to tmux.
        dredmorbius 15y ago
        I can think of a few. If there are problems found with screen (and it's a widely used admin tool that may be left running on remote servers, hence a high-value attack vector), it's going to be harder to find and fix the problem. If there are features to be added, they'll be harder to add to screen than tmux. Which means that with time, tmux stands a higher chance of becoming more featureful. Both argue in favor of tmux in the long run, though there's no immediate need to ditch screen. As you note, screen's very widely available, which is a feature. Then again, so was telnet 10 years ago.
- Nick_C 15y ago
  The only solution I've seen is to start up gdb with the process and point the process's 0, 1 & 2 file descriptors to the shell's STDIN, STDOUT and STDERR, then detach the process and quit gdb. I can't remember the exact details, but that should be enough to set you up for some googling.
obiterdictum 15y ago
You will be pleased to know that there is a site full of little gems like this: http://www.commandlinefu.com/commands/browse/sort-by-votes http://www.commandlinefu.com/commands/browse/sort-by-votes Most of my time savers that I've never thought of were found there.
- michaelty 15y ago
  python -m SimpleHTTPServer Love this one.
  - ryanbraganza 15y ago
    And for you crazy people on python3.. python3 -m http.server
    - ward 15y ago
      [ward@hathor ~]$ ls -l /usr/bin/python lrwxrwxrwx 1 root root 7 Sep 5 00:45 /usr/bin/python -> python3 Arch default
      - freehunter 15y ago
        I think he covered Arch users when he said "crazy people" :)
MPSimmons 15y ago
'man bash' is pretty amazing the first time you actually read through it.
- gnosis 15y ago
  And when you're done with that, try 'man zsh'.
slardat01 15y ago
Didn't know about disown, I always just did an "exec $SHELL" in this case.
- ez77 15y ago
  Could someone explain what this would accomplish? If you have to go offline you would still lose that session, no?

sgt 15y ago

disown is great. However, I don't know if it's possible to start up a new shell, then bring back that process to the foreground. 'jobs' will return no entries, and fg doesn't take a PID parameter. Any ideas? It would be brilliant if that were possible with bash alone.

pja 15y ago
reptyr: https://github.com/nelhage/reptyr https://github.com/nelhage/reptyr is Linux specific & involves a fairly gruesome abuse of ptrace() to attach a running process to your current pty. It won't put the process in the shell jobs list though. There's also retty: http://pasky.or.cz/dev/retty/ http://pasky.or.cz/dev/retty/ but again it's not a complete solution.
xyzzyb 15y ago
disown -h will (reportedly) keep it under job control.
- pja 15y ago
  True, but doesn't help if you've quit the shell & want to re-attach to the process after logging back in again :(
tel 15y ago
Screen is the only real answer, I've ever found.
- gnosis 15y ago
  There's also 'tmux': http://tmux.sourceforge.net/ http://tmux.sourceforge.net/
  - tel 15y ago
    True, screen and screenlikes. I've never used tmux, mostly because screen just works well enough for me.
  - dredmorbius 15y ago
    Which according to reports has the benefit of being maintainable. GNU screen, which I love and use to obscene extents daily, has an exceptionally hairy codebase. That said, I've got to get my tmux on and learn how to do screen equivalents with it.... http://www.techrepublic.com/blog/opensource/is-tmux-the-gnu-screen-killer/1901 http://www.techrepublic.com/blog/opensource/is-tmux-the-gnu-...
    - res0nat0r 15y ago
      I keep seeing people comment on the codebase of screen being bad vs tmux, but I'm not sure why that is an issue? Are there any features of screen missing that haven't been added to the codebase? The vertical split patch has been added a long while back, and even though I'm sure tmux has a smaller memory footprint, I've never had an occasion where screen has ever been an app I'm worried might impact my server memory usage. Since it is installed for the most part everywhere I have no desire to switch to tmux.
      - dredmorbius 15y ago
        I can think of a few. If there are problems found with screen (and it's a widely used admin tool that may be left running on remote servers, hence a high-value attack vector), it's going to be harder to find and fix the problem. If there are features to be added, they'll be harder to add to screen than tmux. Which means that with time, tmux stands a higher chance of becoming more featureful. Both argue in favor of tmux in the long run, though there's no immediate need to ditch screen. As you note, screen's very widely available, which is a feature. Then again, so was telnet 10 years ago.
Nick_C 15y ago
The only solution I've seen is to start up gdb with the process and point the process's 0, 1 & 2 file descriptors to the shell's STDIN, STDOUT and STDERR, then detach the process and quit gdb. I can't remember the exact details, but that should be enough to set you up for some googling.

obiterdictum 15y ago

You will be pleased to know that there is a site full of little gems like this: http://www.commandlinefu.com/commands/browse/sort-by-votes http://www.commandlinefu.com/commands/browse/sort-by-votes Most of my time savers that I've never thought of were found there.

michaelty 15y ago
python -m SimpleHTTPServer Love this one.
- ryanbraganza 15y ago
  And for you crazy people on python3.. python3 -m http.server
  - ward 15y ago
    [ward@hathor ~]$ ls -l /usr/bin/python lrwxrwxrwx 1 root root 7 Sep 5 00:45 /usr/bin/python -> python3 Arch default
    - freehunter 15y ago
      I think he covered Arch users when he said "crazy people" :)

MPSimmons 15y ago

'man bash' is pretty amazing the first time you actually read through it.

gnosis 15y ago
And when you're done with that, try 'man zsh'.

slardat01 15y ago

Didn't know about disown, I always just did an "exec $SHELL" in this case.

ez77 15y ago
Could someone explain what this would accomplish? If you have to go offline you would still lose that session, no?