UNIX for Dummies Questions & Answers

I've just recently started using a Unix server, and I've been trying to figure out how to use the grep command to search a file of mine for all 4-letter words that begin with 's' (I don't care if its uppercase or lowercase) and have an 'r' as the third letter. I've tried many grep variations but none of them have returned properly with what I need. All help is appreciated, thanks.

Although it isn't specified by the standards, many implementations of grep provide a-woption that will restrict matches to strings that contain only alphanumeric characters and the underscore character that appear either at:If this meets your definition of word, then the command:

Code:

grep -w -i 's.r.' input_file

should do what you want.

I don't think its working correctly, it's only returning 3 letter words??

When I put the following in input_file:

Code:

Sir
Siri
treasure
sure
surly
airy

The command:

Code:

grep -w -i 's.r.' input_file

produces the following output:

Code:

Siri
sure

which I believe is what you wanted.
What system are you using?

I'm sorry, I don't believe I know what you mean by system. I'm just using a basic Unix server.... I'm knew to Unix as of last week. I managed to get a hold of a server from a friend of mine. Part of what I would like to do is use the grep command to help find words that can be uppercase and lowercase, that have a certain length, and can contain various letter restrictions (i.e. the third letter being 'r').

Show us:I assume that you're aware that, by default, grep prints entire lines that contain a match for the expression you give.

hi BarrTech,

have you tried this grep -iw "s.r.*" input_file