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I have a code running on a Linux server. Since it takes hours to run, I have to use nohup to make sure my code is still running in case I loose my connection to the server. Again since I have to wait hours to see the results, I defined a counter to print out the progress of my code (%). If I loose my connection to the server or close the terminal, the only way that I can see the code is still running is using top. Is there any way that I can see again the output console (message showing the progress)?

MTT
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    Why not use [GNU screen](http://www.gnu.org/software/screen/) so you can disconnect and reconnect later? – Barmar Feb 05 '15 at 17:50
  • I did not try it! Let me try and I will keep you posted. Thanks. – MTT Feb 05 '15 at 17:53
  • If you have more questions about this, it belongs on superuser.com. It's not a programming question. – Barmar Feb 05 '15 at 17:58

2 Answers2

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You can see the output in real time by running below from another terminal.

tail -f nohup.out
yfpb
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  • that is want! thks – Guihgo Mar 04 '17 at 21:06
  • Thanks. This command just printing realt-timely which is nice. – Fatih Ayyildiz Jan 16 '18 at 19:35
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    Make sure it is executed in the same directory as nohup command because this command reads the output form nohup.out which is generated in the directory. Awesome. Thanks! – Dami May 06 '20 at 14:32
  • What happens if you delete this file? For any new logs, does it create a new `nohup.out` file? – kaushalpranav Oct 17 '21 at 11:16
  • If you delete it, a new one will be created when `nohup` is run again. Otherwise, `nohup` will just keep appending logs to the existing file. At least that's how it is when I tested. – yfpb Oct 18 '21 at 12:15
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You can redirect standard output and standard error to a file and look at that file. eg:

nohup command 2>&1 > outputfile &

note default behavior from man page:

If standard output is a terminal, append output to 'nohup.out' if possible, '$HOME/nohup.out' otherwise. If standard error is a terminal, redirect it to standard output

so really you can just run 

nohup command &

and then look in nohup.out

Mike Atkins
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