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pythonbashsortingcron

Sort crontab -l in order by comment

How do I sort crontab -l in alphabetical order after the last hash mark on each line?

* * * * * curl -m 10 https://google.com # C comment
# * * * * * curl -m 10 https://google.com # A comment
* * * * * curl -m 10 https://google.com # D comment
* * * * * curl -m 10 https://google.com # E comment
* * * * * curl -m 10 https://google.com # Z comment
## * * * * * curl -m 10 https://google.com # B comment
Solution

  • Use awk to prepend each line with the last field, sort on this new 'first' field, then strip this 'first' field from the results:

    $ crontab -l | awk -F'#' '{print $NF"#"$0}' | sort -t'#' -k1,1 | cut -d'#' -f2-
# * * * * * curl -m 10 https://google.com # A comment
## * * * * * curl -m 10 https://google.com # B comment
* * * * * curl -m 10 https://google.com # C comment
* * * * * curl -m 10 https://google.com # D comment
* * * * * curl -m 10 https://google.com # E comment
* * * * * curl -m 10 https://google.com # Z comment

    NOTES:

    • this will treat white space as a sortable character, eg, #<2_spaces>D will be sorted before #<1_space>A
    • with a bit more coding the sort|cut functionality could be rolled into the awk code