Re: [Help-bash] Tackling parameter expansion in functions

[Greg Wooledge]

On Fri, Feb 12, 2016 at 07:14:18PM +0100, Richard Taubo wrote:
> Something like:
> ---------------------
> Test2() {
>     if [ ???$1??? == "this" ]; then
>         word=$("< /dev/urandom tr -dc _A-Z | head -c${1:-7} 
> 2>/dev/null;echo;")
>         printf "$word"
>     fi
> }
> 
> Test2 "this"
> ---------------------

In English?

Are you trying to generate a random password?  Just install something like
https://sourceforge.net/projects/pwgen/ instead of doing this /dev/urandom
nonsense.  Hell, it's even packaged for most Linux distributions.

I think you found a piece of code in another script, and copied it for
your own script, without understanding what it means.

  head -c${1:-7}

means "Show the first $1 characters, or the first 7 characters if no
argument was given."

You can't use $1 to be both "this" and "number of characters".  You would
need to use a separate argument for the "number of characters".

I have utterly no idea why you are comparing $1 to the string "this".