How can I run a function from a script in command line?

Question

I have a script that has some functions.

Can I run one of the function directly from command line?

Something like this?

myScript.sh func()


        

Answer 1

Well, while the other answers are right - you can certainly do something else: if you have access to the bash script, you can modify it, and simply place at the end the special parameter "$@" - which will expand to the arguments of the command line you specify, and since it's "alone" the shell will try to call them verbatim; and here you could specify the function name as the first argument. Example:

$ cat test.sh
testA() {
  echo "TEST A $1";
}

testB() {
  echo "TEST B $2";
}

"$@"


$ bash test.sh
$ bash test.sh testA
TEST A 
$ bash test.sh testA arg1 arg2
TEST A arg1
$ bash test.sh testB arg1 arg2
TEST B arg2

For polish, you can first verify that the command exists and is a function:

# Check if the function exists (bash specific)
if declare -f "$1" > /dev/null
then
  # call arguments verbatim
  "$@"
else
  # Show a helpful error
  echo "'$1' is not a known function name" >&2
  exit 1
fi

Answer 2

you can call function from command line argument like below

function irfan() {
echo "Irfan khan"
date
hostname
}
function config() {
ifconfig
echo "hey"
}
$1

once you function end put $1 to accept argument let say above code is saved in fun.sh to run function ./fun.sh irfan & ./fun.sh config

Answer 3

Edit: WARNING - seems this doesn't work in all cases, but works well on many public scripts.

If you have a bash script called "control" and inside it you have a function called "build":

function build() { 
  ... 
}

Then you can call it like this (from the directory where it is):

./control build

If it's inside another folder, that would make it:

another_folder/control build

If your file is called "control.sh", that would accordingly make the function callable like this:

./control.sh build