Calculations with string values from a config file

Question

I would like to get the time from a config file and the multiply it. When I write the time like 30m it takes case m and uses 30m. But how I can I do calculations with this value.The case s is working as it should.

 getTimeFromConfig(){
case $timestart in
*s )
echo ${timestart::-1};;
*m )
time = ${timestart::-1}
newtime= $(($time*60));;
*h )
time = ${timestart::-1}
newtime= $(($time*3600));;
esac
}

@chroba I added one, it says Row39:1800: command not found (At least it multiplied, but it doesn't echo) — aha364636, Dec 14 '15 at 08:58

score 1 · Answer 1 · answered Dec 14 '15 at 08:58

There shouldn't be any whitespace around = (assignment).

time = ${timestart::-1}
newtime= $(($time*60));;

should be

time=${timestart::-1}
newtime=$(($time*60));;

Similarly,

time = ${timestart::-1}
newtime= $(($zeit*3600));;

should be

time=${timestart::-1}
newtime=$(($zeit*3600));;

If you simply want to print the calculated value then do:

    echo ${newtime}

in each of the case statements of m and h.

If you want this function to "return" the time, you can either use a global variable or print from the function and read it from the caller:

At the end of getTimeFromConfig() do:

    echo ${newtime}
  }

and at the caller:

timevalue=$(getTimeFromConfig)

echo ${newtime}, That was my fault. – aha364636 Dec 14 '15 at 09:05 — aha364636, Dec 14 '15 at 09:05

Calculations with string values from a config file

1 Answers1