How to dynamically name as function in shell?

Shell Programming and Scripting
1

Hi all,

Does anyone know if it possible to append a parameter to a function name?

Something like the following:

function tnsrec_${SERVICE_NAME} {
code..
}

Any ideas?

2

Are you trying to achieve something like this?

# cat test.sh 
function tnsrec_SERVICE1 {
echo "Test ok"
}[

SERVICE_NAME=SERVICE1

eval tnsrec_${SERVICE_NAME}

# ./test.sh 
Test ok
3

hmm, thnx for feedback.

I am supplying a parameter to a script and need to use that parameter to name a function.

In your code, where is the close ']' bracket?

also, when do I place the eval ?

Thanks again.

jd

4

You can't use eval to dynamically name a function in that way.

But why would you want to?

If you can pass any value into a script and thus have a function with any name, why not just chose any name for the function to begin with?

What you are trying to do doesn't really make any sense.

BTW, I think the [ may have been a typo.

5

I need to dynamically name a fnction so a watchdog script can identify a process.

so I need to append a parameter to a function name.

If you have any idea on how to do this I would be grateful.

6 
$ cat myScript
F=${1:-default}

. <(cat <<!
function somefunction_$F {
  echo "\$0: Test OK"
}
!)

eval somefunction_$F

# ./myScript blah
somefunction_blah: Test OK

# ./myScript
somefunction_default: Test OK

This method might be a bit inflexible since you have to escape anything in the function that belongs to the function, otherwise the shell will evaluate it.

Another method, using a temporary functions file:

# cat myScript
F=${1:-default}
sed "s/:name:/$F/" funcs.tmp > funcs.sh

. ./funcs.sh
        
eval somefunction_$F

# cat funcs.tmp
function somefunction_:name: {
  echo "$0: Test OK"
}

# ./myScript blah
somefunction_blah: Test OK
        
# ./myScript 
somefunction_default: Test OK
7

hmm. appending a parameter to a function name is not proving easy.

Ideally I just need 1 script rather than several.

I am getting a little confused.

i would call the script in the following way:

bash myscript SERVICE_NAME

In my script I have:

export SERVICE_NAME=$1

function tnsrec_${SERVICE_NAME} {

..lines of code

}