topic Re: Functions parameters in Operating System - Linux

Functions parameters

Leo The Cat — Thu, 23 Apr 2009 13:15:00 GMT

Hi

My function below must return $2 if $1 is null.

nvl() {

if [[ $1 == "" ]]; then
return $2
else
return $1
fi

}

echo $(nvl $test "null")

What is the correct syntax ?

Bests Regards
Den

Re: Functions parameters

Steven Schweda — Thu, 23 Apr 2009 14:15:42 GMT

> What is the correct syntax ?

It depends on exactly what you're trying to
do. Are you looking for something like this?

bash$ nvl() {
> if [ -z "$1" ]; then
> return "$2";
> else
> return "$1";
> fi
> }

bash$ nvl 23 34 45
bash$ echo $?
23

bash$ nvl '' 45 56
bash$ echo $?
45

Is there some actual problem which you are
trying to solve? Asking how to implement
some particular (bad) solution to a problem
may not be the best way to get a good
solution to that problem.

Re: Functions parameters

Heironimus — Thu, 23 Apr 2009 15:38:03 GMT

If you want the function to match how you're using it you need to echo instead of return.