CODEWITHSUNDEEP
regexgrep
Doe
Doe

Reputation: 9

Grep Regular Expressions

I'm trying to show all phone numbers with two nonconsecutive "-" in it. I've tried these expressions:

grep '[-]{2}' phones.txt
grep '-{2}' phones.txt
grep '.*[-].+[-].+$' phones.txt
grep '^\d+[-]\d+[-]\d+$' phones.txt

But none are working. This is my first time using regular expressions and I'm not sure where I'm going wrong

Upvotes: 0

Views: 1215

Answers (2)

dave
dave

Reputation: 11995

You could try something like:

grep '^.*-.*-.*$' phones.txt

This will find the case where the - are adjacent and not. The - can also be at the beginning or end.

If you're looking to restrict it to numbers like:

123-555-3456

ie. the - are in the "middle" and separated by digits, you can use the more restrictive:

grep '[0-9]\+-[0-9]\+-[0-9]\+' phones.txt

For my sample phones.txt:

012-345-678
012-345
012-345-
-012-345
012345
543838--499
--
1-2-3

the second pattern matches the following:

012-345-678
1-2-3

I'm using: grep (GNU grep) 2.4.2

Upvotes: 3

miltonb
miltonb

Reputation: 7385

Non consecutive or consecutive can be matched with (--?). This is a - character followed by a - which can exist zero or 1 times (optionally followed by).

Upvotes: 0

Related Questions