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rɑːdʒɑ
Asked: 2015-03-13 04:37:42 +0800 CST

using watch run 2 commands

  • 772

I have to do watch two commands in the same terminal windows. I mean something like 

watch du -h filename.txt && df -h

But its showing only one output.

So what I am thinking is may be its not possible to use watch to run multiple commands on the same window.

If there is any way , Please let me know.

Thank you.

command-line

4 Answers

  1. Best Answer

    You can quote the commands:

    watch "du -h filename.txt && df -h"

    And they'll be executed together.

    • 106

  2. If you want to make sure both commands execute, one of the ways is to separate them with ; instead of &&.

    watch 'du -h filename.txt; df -h'

    && allows the execution of second command (second operand, to the right of &&) only if the first command executed successfully (exit status 0). If this is intended behaviour, go with &&.

    • 26

  3. For completeness sake...

     watch 'du -h filename.txt || true && df -h'

    The '|| true' part causes the first command to evaluate as true even if it fails for some reason. This will allow the next command after the && to execute no matter the output of first. This is most likely unnecessary for the scenario, just showing it to be possible.

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  4. For multiple commands to run simultaneously, use single & operator between the commands. Like:

    dothis & dothat

    To clear any confusion, here's how different operators work:

    c1 & c2  # Run both commands parallelly
c1 ; c2  # Run both commands one by one
c1 && c2 # Run c2 only if c1 exits successfully
c1 || c2 # Run c2 only if c1 fails
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