Parse ps' “etime” output and convert it into seconds

Question

These are possible output formats for ps h -eo etime

21-18:26:30
   15:28:37
      48:14
      00:01

How to parse them into se

Answer 1

Try to use my solution with sed+awk:

ps --pid $YOUR_PID -o etime= | sed 's/:\|-/ /g;' |\ 
awk '{print $4" "$3" "$2" "$1}' |\
awk '{print $1+$2*60+$3*3600+$4*86400}'

it splits the string with sed, then inverts the numbers backwards ("DD hh mm ss" -> "ss mm hh DD") and calculates them with awk.

$ echo 21-18:26:30 | sed 's/:\|-/ /g;' | awk '{print $4" "$3" "$2" "$1}' | awk '{print $1+$2*60+$3*3600+$4*86400}'
1880790
$ echo 15:28:37 | sed 's/:\|-/ /g;' | awk '{print $4" "$3" "$2" "$1}' | awk '{print $1+$2*60+$3*3600+$4*86400}'
55717
$ echo 48:14 | sed 's/:\|-/ /g;' | awk '{print $4" "$3" "$2" "$1}' | awk '{print $1+$2*60+$3*3600+$4*86400}'
2894
$ echo 00:01 | sed 's/:\|-/ /g;' | awk '{print $4" "$3" "$2" "$1}' | awk '{print $1+$2*60+$3*3600+$4*86400}'
1

Also you can play with sed and remove all non-numeric characters from input string:

sed 's/[^0-9]/ /g;' | awk '{print $4" "$3" "$2" "$1}' | awk '{print $1+$2*60+$3*3600+$4*86400}'