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# 1  
Old 05-19-2006
question on egrep
Hi
I am trying to use this command:
egrep '^a{2,6}$' testexpr4D

to retreive lines with 2,3,4,5, or 6 a's in a file .
The file testexpr4D has entries like:
a
aa
aaa
aaaa
aaaaa
aaaaaa
123456
ABCDEF

I was expecting to see 5 lines in the output but nothing happens.
Can anyone help please?
Thanks
Rohit
# 2  
Old 05-19-2006
Code:
egrep '^a\{2,6\}$' testexpr4D

# 3  
Old 05-19-2006
question on egrep
Hi Shreenmotor,
That doesn't work either !

Thanks
Rohit
# 4  
Old 05-19-2006
This works:
Code:
 egrep '^(a)(a)?' filename

test:
Code:
kcsdev:/home/jmcnama> cat filename
a
aa
aaa
aaaa
aaaaa
aaaaaa
123456
ABCDEF



kcsdev:/home/jmcnama> egrep '^(a)(a)?' filename
a
aa
aaa
aaaa
aaaaa
aaaaaa

Note:
Code:
 egrep '^(a)+$' filename

is closer to correct - correct being 'find a line of any non-zero length that has only the letter a'
Last edited by jim mcnamara; 05-19-2006 at 04:36 PM..
# 5  
Old 05-22-2006
question on egrep
Jim,
Your solution fetches all the a's in a file . I need to fetch the lines with
2 to 6 a's in a line
Rohit
# 6  
Old 05-22-2006
Quote:
Originally Posted by shereenmotor
Code:
egrep '^a\{2,6\}$' testexpr4D

shereenmotor, that solution is pretty close, but no cigar !

You are mixing the syntax's of sed and [e]grep.

If it were sed, it would be

Code:
sed -n -e "/^a\{2,6\}$/p" filename

If it were grep it would be

Code:
egrep '^a{2,6}$' filename

# 7  
Old 05-22-2006
put one 'a'
Put a single a before the mentioned pattern. You should get your result.
egrep '^a(a)+$' filename
 
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