[SOLVED] Exit function if no arguments passed in

kzo81 · 11-26-2016, 07:29 AM

Hi,

I wrote this:

#!/bin/bash

function check_args(){

if [ $# -eq 0 ]; then
echo "No arguments passed"

fi
}

check_args

and interestingly if I run it like this:

./testing a b c

it still goes into the if, but why??? I have passed in 3 arguments :-)

Please help me out!

Thanks,

Zoli

grail · 11-26-2016, 07:57 AM

You passed 3 to the script, but none to the function which has its own copy of $#

kzo81 · 11-26-2016, 09:18 AM

Quote:

Originally Posted by grail

You passed 3 to the script, but none to the function which has its own copy of $#

Yes! True. Thanks, could you help me how to organise this argument check function the way I wrote?

I like bash scripts this way:

Code:

function a(){
echo 'a'
}

function b(){
echo 'b'
}

function main(){
a
b
}

main

pan64 · 11-26-2016, 09:29 AM

please use [code][/code] tags around your code!
you need to pass the arguments to the function (for example):

Code:

function check_args(){
  if [ $# -eq 0 ]; then
    echo "No arguments passed"
  fi
}

check_args "$@"

kzo81 · 11-26-2016, 09:54 AM

Code:

check_args "$@"

thanks!!

pan64 · 11-26-2016, 10:03 AM

glad to help you

if you want to say thanks just click on yes
if you think your problem is solved, please mark thread as solved.

kzo81 · 11-26-2016, 10:49 AM

For some reason it still doesn't accept 3 arguments

https://github.com/kerzol81/Bash-and...r_and_arranger

pan64 · 11-26-2016, 11:11 AM

because main is a function too and you need to pass arguments to main too.

kzo81 · 11-26-2016, 11:34 AM

Thanks! I thought I only need to pass in the arguments only when I define main.

pan64 · 11-26-2016, 12:18 PM

as it was already mentioned (in post #2) all the functions have their own arguments, "$@" means the argument list passed to the actual function (or to the script itself).

JeremyBoden · 11-26-2016, 01:34 PM

But $# is the number of arguments passed.

grail · 11-26-2016, 01:49 PM

Quote:

Originally Posted by JeremyBoden

But $# is the number of arguments passed.

Not sure what the purpose of this post was? Are you simply stating the fact?