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Full Discussion: if condition in a while loop
Top Forums Shell Programming and Scripting if condition in a while loop Post 302472141 by ygemici on Tuesday 16th of November 2010 11:25:55 AM
Old 11-16-2010
Quote:
Originally Posted by cfajohnson
It's an inefficient way of getting the first three characters of "$line".

It will not do what is wanted if the number of characters before the comma is anything other than 3.

A more efficient (and portable) method uses parameter expansion instead of an external command:
Code:
grp=${line%"${line#???}"}

I dont agree your comment about inefficient way..
Why do you think such as?
Sed is external command but it has same effect every shells.

svajhala already wants process for only first three chars..

Maybe more portable or maybe not..If we hope to do every jobs from shell , it is not exactly true according to me.
 

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