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Bash script problems with "if" statement

Hi there.

I've been trying to get a script of mine working. The part that doesn't work (below) is involved with determining how long the script was running for. Here is the code:

Code:

#!/bin/sh



TOTAL_HOURS=-22

TOTAL_MINUTES=-10



#If TOTAL_HOURS is negative then add 24 to it

if [ "$(TOTAL_HOURS)" -lt "0" ];then

        TOTAL_HOURS= `expr $(TOTAL_HOURS) + 24`

fi



#If TOTAL_MINUTES is negative then add 60 to it and takeaway 1 from TOTAL_HOURS

if [ "$(TOTAL_MINUTES)" -lt "0" ];then

        TOTAL_HOURS= `expr $(TOTAL_HOURS) - 1`

        TOTAL_MINUTES= `expr $(TOTAL_MINUTES) + 60`

fi



#Formulate the total time taken into one line

TOTAL_TIME=`echo $TOTAL_HOURS`h`echo $TOTAL_MINUTES`m



#Output TOTAL_TIME to stdout

echo $TOTAL_TIME

The output I get from this is:

Code:

adz@hades:~/temp$ ./test 

./test: line 1: TOTAL_HOURS: command not found

./test: line 7: [: : integer expression expected

./test: line 1: TOTAL_MINUTES: command not found

./test: line 12: [: : integer expression expected

-22h-10m

The output I want from it is just "1h50m". I've tried with and without the brackets around the variable name in the expr expression. I'm convinced it's something simple but I can't put my finger on it.

All I did was remove the quotes around the $VARIABLES (makes only cosmetic differences in this case) and especially the $(parentheses); $() is similar to backticks; both are forms of command substitution. You were trying to execute TOTAL_HOURS and TOTAL_MINUTES :).

Code:

#!/bin/sh



TOTAL_HOURS=-22

TOTAL_MINUTES=-10



#If TOTAL_HOURS is negative then add 24 to it

if [ $TOTAL_HOURS -lt 0 ];then

        TOTAL_HOURS=`expr $TOTAL_HOURS + 24`

fi



#If TOTAL_MINUTES is negative then add 60 to it and takeaway 1 from TOTAL_HOURS

if [ $TOTAL_MINUTES -lt 0 ];then

        TOTAL_HOURS=`expr $TOTAL_HOURS - 1`

        TOTAL_MINUTES=`expr $TOTAL_MINUTES + 60`

fi



#Formulate the total time taken into one line

TOTAL_TIME=`echo $TOTAL_HOURS`h`echo $TOTAL_MINUTES`m



#Output TOTAL_TIME to stdout

echo $TOTAL_TIME

HTH!

Brilliant. I knew it was something simple. I was sure I tried your solution previously but maybe buggered something else up. Thanks.