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grep with wilcard character(*)

 
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# 1  
Old 07-08-2008
grep with wilcard character(*)
Hello people,
I am trying to grep out a certain pattern from some files. The situation is like this:
constantstring1<random data>constantstring2
I am using the following command (which clearly is not working!!!):
datestring=<some date in YYYYMMDD format>
searchstring=$datestring"*_xyz"
grep -hc $searchstring a.txt

Can you also be kind enough to give a short explanation for the solution?
Thanks a lot.
# 2  
Old 07-08-2008
You have to put a dot in front of the wildcard.
. means any character, but only one,
* means the former character zero times or multiple occurence
Ie. it's ".*" not "*".

Best have the pattern in grep in " " too and the variable written like ${myvar} to avoid problems.
# 3  
Old 07-08-2008
Thanks a lot man!!!
 
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