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awk and regex to find out file extension

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# 1  
Old 12-26-2010
awk and regex to find out file extension
From following data, I want to only publish those lines in which column 6 has the value with extension .dat.
Code:
col1,col2,col3,col4,col5,col6.txt,col7,col8
col1,col2,col3,col4,col5,col6.date,col7,col8
col1,col2,col3,col4,col5,col6.jpg,col7,col8
col1,col2,col3,col4.dat,col5,col6.dat,col7,col8
col1,col2,col3,col4,col5,col6.date,col7,col8

I am trying with following statement:
Code:
awk 'BEGIN { FS = "," }{if ($6 == /^*\.dat$/ ) {print $6;}}' tt.txt

In above tt.txt contains the above data.

regards
Last edited by Scott; 12-26-2010 at 09:31 AM.. Reason: Code tags, please...
# 2  
Old 12-26-2010
Code:
$ awk -F, '$6 ~ /\.dat$/ {print $6}' tt.txt
col6.dat

This User Gave Thanks to Scott For This Post:
fahdmirza
# 3  
Old 12-26-2010
Thanks for your answer.
Would you please tell me what was the problem with my regex? Why * is not needed? Because * is for zero or more occurrence of any thing.

regards
# 4  
Old 12-26-2010
* does not have the same meaning as in filename expansion. In a regular expression, it matches 0 or more occurrences of the previously matched expression. You didn't try to match any expression. . (dot) is used to match "anything". * will match 0 or more of them.

Code:
.*    # match 0 or more of any character

In any case, you only want to find things ending in .dat, so that's all you have to look for.
This User Gave Thanks to Scott For This Post:
fahdmirza
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