bash built in function bash source code

Question

How to find source of a built in bash function?

I know that it is a function:

$type -t MY_APP
function

I see it's code:

type MY_APP
code

The questions are:

1. Where is it stored?
2. How can I modify it?

Answer 1

You can do it like this:

# Turn on debug
$ shopt -s extdebug

# Print out the function's name, line number and file where it was sourced from
$ declare -F my_function
my_function 46 /home/dogbane/.bash/.bash_functions

# Turn off debug
shopt -u extdebug

To edit the function, open the file containing the function definition (that you found from above). Edit the function and save the file. Then source it into your shell, like this:

$ . /path/to/function_file