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Need help in Regular expression in bash shell

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Top Forums Shell Programming and Scripting Need help in Regular expression in bash shell
# 1  
Old 07-26-2010
Need help in Regular expression in bash shell
hi,

I have written a script to search MAC address in a given directory.
MAC address would be in format XX.XX.XX.XX.
The digits contain hexadecimal numbers.
For this i have used grep as follows.
Code:
 
 
grep -rn '^[0-9A-F]\{1,2\}\.[0-9A-F]\{1,2\}\.[0-9A-F]\{1,2\}\.[0-9A-F]\{1,2\}\$' *

This is not working as required. It is not fetching any output though the files contain MAC address.

If i give,

Code:
 
grep -rn '^[0-9A-F]\{1,2\}\.[0-9A-F]\{1,2\}\.[0-9A-F]\{1,2\}\.*' *

The above command is also giving 3.23.AS.AA

where S is not specified in the regular expression.
# 2  
Old 07-26-2010
You are missing a dot at this position:
Code:
grep -rn '^[0-9A-F]\{1,2\}\.[0-9A-F]\{1,2\}\.[0-9A-F]\{1,2\}\.*' *
                                                              ^
                                                              |
                                                            here

You want
Code:
\..*

but you have
Code:
\.*

There is also a nice POSIX expression for hexadecimal numbers:
Code:
[[:xdigit:]]

Just a side note regarding your topic (no biggie - just to clarify):
This regular expressions are from the grep command, not the bash shell Smilie
# 3  
Old 07-26-2010
Thanks Zaxxon...

The second part is solved.

Can you please look at the first part.

Code:
grep -rn '^[0-9A-F]\{1,2\}\.[0-9A-F]\{1,2\}\.[0-9A-F]\{1,2\}\.[0-9A-F]\{1,2\}\$' *

I want to search for patterns XX.XX.XX.XX
Where X can be hexadecimal numbers.
# 4  
Old 07-26-2010
Code:
grep -Ern "\<[0-9A-F]{1,2}(\.[0-9A-F]{1,2}){3}\>" urfile

# 5  
Old 07-26-2010
Thanks rdcwayx... Smilie
This is working if the MAC address is in the beginning of the line...

Suppose if the MAC adrress in between, it is not shown in the output Smilie
# 6  
Old 07-26-2010
I see no further problem so far:

Code:
$> cat infile
lalala
here is a mac address 00.30.05.be.c5.bc ok?
rubbish
here is not a mac address 00.30.0s.be.c5.bc ok?
another 00.30.05.be.c5.b1 ok?
litter
$> grep -i '[0-9A-F]\{1,2\}\.[0-9A-F]\{1,2\}\.[0-9A-F]\{1,2\}\..*' infile
here is a mac address 00.30.05.be.c5.bc ok?
another 00.30.05.be.c5.b1 ok?

Smilie

After adding the 2nd dot there was no problem anymore.
# 7  
Old 07-26-2010
Code:
# cat macfile
AF.86.3D.91.
3.23.AS.AA

you can try this Smilie

Code:
# grep -rn '[0-9a-fA-F][0-9a-fA-F].\{4\}' macfile
1:AF.86.3D.91.



---------- Post updated at 04:30 PM ---------- Previous update was at 04:28 PM ----------

Code:
# cat macfile
lalala
here is a mac address 00.30.05.be.c5.bc ok?
rubbish
here is not a mac address 00.30.0s.be.c5.bc ok?
another 00.30.05.be.c5.b1 ok?
litter

Code:
# grep -rn '[0-9a-fA-F][0-9a-fA-F].\{4\}' macfile
2:here is a mac address 00.30.05.be.c5.bc ok?
4:here is not a mac address 00.30.0s.be.c5.bc ok?
5:another 00.30.05.be.c5.b1 ok?
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