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Regex not working

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# 1  
Old 10-11-2013
Wrench Regex not working
I am using a regex to exactly match a string abcdef as
Code:
^abcdef$

. But it does'nt seem to work Smilie
# 2  
Old 10-11-2013
In your case
Code:
^abcdef

that is enough.
The start AND end definitions are only required if you pass the start AND the end of a the string to search, meaning an incomplete one or one holding further variables.

That would be done by:
Code:
^abc.xyz$

Matching each line starting with abc AND ending with xyz ;
regardless if there is the alphabet in between or not.

Hope this helps
# 3  
Old 10-11-2013
What input do you have ?
What output do you expect ?
Please provide a representative sample so people may then be able to help you to achieve what you want.
# 4  
Old 10-11-2013
In what computer language? bash / ksh93 shell?
Code:
str=abcdef
if [[ $str =~ ^abcdef$ ]]; then
  echo match
fi

# 5  
Old 10-11-2013
I tried the
Code:
^abcdef

first but then it matched other strings like
Code:
abcdefghi

. So I wanted to match the exact string.

I tried to put in
Code:
ab.ghi

. Still not working.Smilie Please help.
# 6  
Old 10-11-2013
did you try with the dollar sign at the end ?

Code:
^abcdef$

If you states it's not working, could you please show us exactly how you test the matching ?
Code:
$ cat toto
gfedcba
abcdefg
abcdef
abcdefg
Abcdef
fgqjghjk
rueaioyu
$ grep ^abcdef$ toto
abcdef
$

Last edited by ctsgnb; 10-11-2013 at 04:54 PM..
# 7  
Old 10-11-2013
Weird thing is, it didnt work at first..
But now does..

Code:
+ ~ $ echo abcdefg|grep ^abcdefg
abcdefg
:) ~ $ echo abcdefg|grep ^abcdefg$
abcdefg
✔ ~ $ echo abcdefg|grep ^abc.efg$
abcdefg
✔ ~ $ echo abcdefg|grep ^abc*fg$
:( ~ $ echo abcdefg|grep ^abc.fg$
- ~ $ echo abcdefg|grep ^abc.efg$
abcdefg
✔ ~ $ echo abcdefg|grep ^abc?efg$
- ~ $

hth
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