How to call a function in shell Scripting?

Question

I have a shell script which conditionally calls a function.

For Example:-

if [ "$choice" = "true" ] then    process_install elif [ "$choice" = "false" ] then    process_exit fi  process_install() {   commands...   commands... }  process_exit() {   commands...   commands... } 

Please let me know how to accomplish this.

Answer 1

You don't specify which shell (there are many), so I am assuming Bourne Shell, that is I think your script starts with:

#!/bin/sh 

Please remember to tag future questions with the shell type, as this will help the community answer your question.

You need to define your functions before you call them. Using ():

process_install() {     echo "Performing process_install() commands, using arguments [${*}]..." }  process_exit() {     echo "Performing process_exit() commands, using arguments [${*}]..." } 

Then you can call your functions, just as if you were calling any command:

if [ "$choice" = "true" ] then     process_install foo bar elif [ "$choice" = "false" ] then     process_exit baz qux 

You may also wish to check for invalid choices at this juncture...

else     echo "Invalid choice [${choice}]..." fi 

See it run with three different values of ${choice}.

Good luck!

Answer 2

#!/bin/bash  process_install() {     commands...      commands...  }  process_exit() {     commands...      commands...  }   if [ "$choice" = "true" ] then     process_install else     process_exit fi