Korn Shell Programming by Example

User Input

Getting input through to your teenager may require anything from a gentle tap on the shoulder to a shouted “Wassup?” But either way, the ultimate goal is to alter the behavior based on the input you supply. A shell script may be written such that it requires no input from the user. An example would be the masks_magic script from the previous chapter. A sample run is shown to refresh your memory:

$ mask_magic
Default regular file permissions with current umask (0002)
u  g  o
_________
rwxrwxrwx
110110100

Default directory file permissions with current umask (0002)
 u  g  o
_________
rwxrwxrwx
111111101

1s are on, 0s are off
$

Or it can be written so that it checks the contents of certain environment variables and branches inside of the ...