------------------------------------------

$ ls -l a
---x------ 1 toaq None 24 Apr  6 14:29 a

toaq@comp ~
$ cat a
#/usr/bin/bash
echo abc

toaq@comp ~
$ ./a
abc

toaq@comp ~
$

------------------------------------------
toaq@comp ~
$ ls -l a2
-r-------- 1 toaq None 9 Apr  6 14:33 a2

toaq@comp ~
$ cat a2
echo abc

toaq@comp ~
$ ./a2
abc

toaq@comp ~
$
------------------------------------------