UNIX for Dummies Questions & Answers

Hey can someone explain this script to me.
I don't understand it fully. I'm a newbie

Code:

#!/bin/bash

ex $1 << '@'
1,$ !egrep '\.jsp' | cut -f1 -d" " | sort | uniq
1,$p
q!
@

This is a very strange way to use the ex-editor (the command line version of vi) to process a file.

The commands delimited with '@' form a here-document, which is the command input to 'ex'. The first command sends all lines of the file throught the pipeline egrep '\.jsp' | cut -f1 -d" " | sort | uniq. The result replaces the previous contents of the file in memory. Then all lines are printed and finally the file is NOT saved.

The same result could be gained with this script:

Code:

#!/bin/bash
egrep '\.jsp' $1 | cut -f1 -d" " | sort | uniq

It would be faster too, because 'ex' maintains undo-information which takes a lot of time, if the file processed is big.

Oke thanks for the response!