Calculations with string values from a config file [duplicate]

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
}

@123 What do you mean?

aha364636
– aha364636

2015-12-14 08:45:29 +00:00
Commented Dec 14, 2015 at 8:45 — aha364636
– aha364636, Commented Dec 14, 2015 at 8:45
What's the problem/error you face?

P.P
– P.P

2015-12-14 08:47:31 +00:00
Commented Dec 14, 2015 at 8:47 — P.P
– P.P, Commented Dec 14, 2015 at 8:47
@l3x I don't know how to calculate if I use it with -1

aha364636
– aha364636

2015-12-14 08:51:41 +00:00
Commented Dec 14, 2015 at 8:51 — aha364636
– aha364636, Commented Dec 14, 2015 at 8:51
What's this function supposed to do? Do you get any errors?

P.P
– P.P

2015-12-14 08:54:16 +00:00
Commented Dec 14, 2015 at 8:54 — P.P
– P.P, Commented Dec 14, 2015 at 8:54
There's no echo for the m and h cases.

choroba
– choroba

2015-12-14 08:55:32 +00:00
Commented Dec 14, 2015 at 8:55 — choroba
– choroba, Commented Dec 14, 2015 at 8:55

P.P · Accepted Answer · 2015-12-14 08:58:26Z

1

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)

answered Dec 14, 2015 at 8:58

P.P

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1 Comment

aha364636 Over a year ago

echo ${newtime}, That was my fault.

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