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how do I filter for a specific line in a file?

 
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# 1  
Old 06-19-2008
how do I filter for a specific line in a file?
It seems like it should be very simple to have a command like grep return a specific line from a file but I can't find anything in the man pages to make grep search by line. I've looked in cat as well. Anyone know how to return a single line from a file?
# 2  
Old 06-19-2008
I'd also like to add that I want to be able to find the nth line in a file where n is a shell variable.
# 3  
Old 06-19-2008
more +n file|head -1
# 4  
Old 06-25-2008
Strange, my head command on Mac OS doesn't seem to take std input on this. Each command works fine alone. Here's what I used:

>cat b
1
2
3
4
5

>more +3 b | head -1
1

Odd? Seems like it should give
3

>more +3 b
3
4
5

This works good. Now running head -1 should just give the first line. Bug or me?
# 5  
Old 06-25-2008
more does the same as cat when followed by a pipe, the +n does nothing in this case.
# 6  
Old 06-26-2008
Will this work for your project?

$ cat myfile
1
2
3
4
5
$ sed -n '3p' myfile
3
Last edited by eBay; 06-26-2008 at 07:38 PM..
 
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