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Jags avatar Ubuntu

Bash: Define a function in bashrc that can be used by any scripts globally

kp flag
Jags

I like to define a function in ~/.bashrc and use it in different scripts either via export -f or source .bashrc.

The function:

nano ~/.bashrc

function test_func() {
    yt-dlp -f '299+140' --merge-output-format mp4 -cia List.txt;
}

export -f test_func

The script:

#!/bin/bash

cd /home/admn/Downloads/YT_DL;

test_func --autonumber-start 101 -o '%(autonumber)1d_%(title)s.%(ext)s';

Problem-1:

After test_func, rest of the command --autonumber-start 101 -o '%(autonumber)1d_%(title)s.%(ext)s' is not working at all.

Problem-2:

Earlier when I tried to use source .bashrc in my script, I was getting these errors:

/usr/local/scripts/test.sh: line 3: .bashrc: No such file or directory
/usr/local/scripts/test.sh: line 12: test_func: command not found

The function (without export -f):

nano ~/.bashrc

function test_func() {
    yt-dlp -f '299+140' --merge-output-format mp4 -cia List.txt;
}

The script (with source .bashrc):

#!/bin/bash

source .bashrc

cd /home/admn/Downloads/YT_DL;

test_func --autonumber-start 101 -o '%(autonumber)1d_%(title)s.%(ext)s';

Edit-1:

$ bash -xv /usr/local/scripts/test.sh
#!/bin/bash

source /home/admn/.bashrc
+ source /home/admn/.bashrc
# ~/.bashrc: executed by bash(1) for non-login shells.
# see /usr/share/doc/bash/examples/startup-files (in the package bash-doc)
# for examples

# alias pip='pip3.7'
alias python='python3'
++ alias python=python3

# If not running interactively, don't do anything
case $- in
    *i*) ;;
      *) return;;
esac
++ case $- in
++ return

test_func --autonumber-start 101 -o '%(autonumber)1d_%(title)s.%(ext)s';
+ test_func --autonumber-start 101 -o '%(autonumber)1d_%(title)s.%(ext)s'
/usr/local/scripts/test.sh: line 5: test_func: command not found
$

These are some of the threads I have gone through; and though I've got some ideas, I still couldn't work out a solution for my use case. Thanks.

https://unix.stackexchange.com/questions/63665/how-to-define-a-bash-function-that-can-be-used-by-different-scripts

https://stackoverflow.com/questions/6218268/how-to-define-a-bash-function-for-use-in-any-script

https://stackoverflow.com/questions/17219174/variables-set-in-bashrc-and-accessing-them-in-shellscript

https://stackoverflow.com/questions/1500499/how-do-you-call-a-function-defined-in-bashrc-from-the-shell

Define a globally available bash function to be used by any script

OS: Ubuntu MATE 21.04

Bash: 5.1.4(1)-release (x86_64-pc-linux-gnu)

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Score:3
avatar Ubuntu
tm flag
choroba

If you want the function to use parameters, you need to explicitly mention them.

function test_func() {
    yt-dlp "$@" -f '299+140' --merge-output-format mp4 -cia List.txt
    #      ~~~~
}

"$@" stands for "all the parameters", you can also use positional parameters like "$1", "$2", etc.

If you source a file from a different directory, you need to either specify a full path to it, or have the file's path in $PATH.

source ~/.bashrc
# or
PATH+=:~
source .bashrc

After the update: Your .bashrc contains a return that stops processing the .bashrc if not running in an interactive shell. Put the function declaration somewhere before the condition if you want to execute it in non-interactive shells, too.

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tm flag
choroba
Try running your scripts under `set -xv` so you see what commands are being run.
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tm flag
choroba
The `return` exits the `.bashrc` before it gets to the function declaration.
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tm flag
choroba
Your `.bashrc` contains `return` that stops processing the `.bashrc` if not running in an interactive shell. Put the function declaration somewhere before the condition if you want to execute it in non-interactive shells, too.
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Jags avatar
kp flag
Jags
posting function before `return` condition solved it. So, does this part `# If not running interactively, don't do anything | case $- in | *i*) ;; | *) return;; | esac` needs to go at the end of `.bashrc` file? Thank you so much.
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Jags avatar
kp flag
Jags
Lastly, is there a "preferred / standard / better" way to call function from `.bashrc`? I mean, `export -f` vs `source ~/.bashrc` Thanks
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tm flag
choroba
The "return" part should go before the stuff you want in an interactive shell, but don't want in a non-interactive one.
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tm flag
choroba
I'm no expert but I prefer `source` to `export`.
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Jags avatar
kp flag
Jags
That's what I read in few places too that `source` is preferred/better way. Thank you so much :)
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