Re: non-executable files in $PATH cause errors

[Greg Wooledge]

I give up trying to quote appropriate context.  Here's what bash 5.0
is doing:

unicorn:~$ echo "$PATH"
/home/greg/bin:/usr/local/bin:/usr/bin:/bin:/usr/local/games:/usr/games:/sbin:/usr/sbin
unicorn:~$ type moo
bash: type: moo: not found
unicorn:~$ echo "echo Moooo" > ./bin/moo
unicorn:~$ moo
bash: /home/greg/bin/moo: Permission denied
unicorn:~$ type moo
moo is hashed (/home/greg/bin/moo)

Whether that's correct behavior or not, I can't even guess.

As far as the historical usage of ":" vs. "#!", I would trust Sven
Mascheck's page over all other sources.

https://www.in-ulm.de/~mascheck/various/shebang/

It links to an old "Unix FAQ" that explains the history of the ":" thing,
but Sven's page disputes some of the FAQ's explanation.  You'll need to
read both pages to get the full picture.