Example
In helloWorld.sh
#!/bin/bash
# Define a function greet
greet ()
{
echo "Hello World!"
}
# Call the function greet
greet
In running the script, we see our message
$ bash helloWorld.sh
Hello World!
Note that sourcing a file with functions makes them available in your current bash session.
$ source helloWorld.sh # or, more portably, ". helloWorld.sh"
$ greet
Hello World!
You can export a function in some shells, so that it is exposed to child processes.
bash -c 'greet' # fails
export -f greet # export function; note -f
bash -c 'greet' # success
