Pattern Matching


 
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Top Forums Shell Programming and Scripting Pattern Matching
# 1  
Old 04-12-2009
Pattern Matching

Hi, I'm very new to Linux and I'm sorry if this question is too dumb.
If it is ok, please link me to some beginner guides for questions like this one.

I want to check if the entered string is a number and has 4 digits.

I heard that I should use "regular expression" or something like that to accomplish this task, but I don't know how to use it.

Code:
echo -n "Input: ";read x
if [ $x == ${...err i dont know what to put here} ];then echo "Valid"
else echo "Invalid";fi

Any help is much appreciated! Smilie
# 2  
Old 04-12-2009
# 3  
Old 04-12-2009
Oh. I'm sorry didn't know this forum is not for beginners.
# 4  
Old 04-12-2009
This forum is for beginners. This seems like a classic "check this string to see if it is valid" homework assignment.
# 5  
Old 04-12-2009
# 6  
Old 04-12-2009
Thank you. I was searching a while actually. But seems like no one talks about this. Is it too simple or something?

And why is that "homework" thing is such big deal anyways? If I say it's not a homework and I want to ask just simply because I don't know how to do it and I need some help, then it's not a homework. But I'm not gonna lie, it's my homework, a part of my project.
# 7  
Old 04-12-2009
Quote:
Results 1 - 10 of about 6,930,000 for regular expressions. (0.13 seconds)
No one talks about this?

Either way, if we help you with your homework, and you get a good degree and a well paying job, are you going to pay us for our work? Or are you going to keep coming here for answers for your job? What would your professor think about this situation? Your boss?

edit by bakunin:

First off, many thanks for doing my job. If you want to become a moderator and boss around forum users (just the same way i do right now with you) just ask Neo. Until you are officially part of the evil side of things (i.e. forum moderation team) please tone it down a bit and at least try to be friendly.

Second: we all have started somewhere sometimes and just because a beginner is a beginner it does not mean his problem is homework. Which - if not uninformed - questions is a beginner supposed to ask? The thread owner did not ask for a solution he asked where he can learn what he need to know to solve it himself. The thread owner has at least tried to do his work himself and wrote a script as far as he got with it.

Third: You try to act as a moderator here but neglect the most basic rules yourself: you post - repeatedly - completely off-topic just to chastise someone. This might not be a beginners forum and it is definitely no homework-forum, but neither is it a holier-than-you-forum and it is no show-off-your-big-ego-forum.

This is a forum to help one another and i would ask you to honor this spirit of the board.

Last edited by bakunin; 04-12-2009 at 09:39 AM..
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