How to grep for case insensitive string in a file?

Question

I have a file file1 which ends with Success... OR success...

I want to grep for the word success in a way which is not case sensitive way.

I have written the following command but it is case sensitive

cat file1 | grep "success\.\.\."

How can i change it so that it returns 0 with both Success... OR success...

Solution 1

You can use the -i flag which makes your pattern case insensitive:

grep -iF "success..." file1

Also, there is no need for cat. grep takes a file with the syntax grep <pattern> <file>. I also used the -F flag to search for a fixed string to avoid escaping the ellipsis.

Solution 2

For me SQL=echo $line | grep -iF "SQL"; IT works perfect

Comments

[User123]

doesn't simple grep -i success file1 returns the same output as expected here?

[Nic]

@User123 Yes, but -F searches for the exact string, without doing any regex parsing, so it's often faster and easier to type if you (as the OP did) have special characters in the phrase you're looking for

[ashleedawg]

could you explain what this is doing?

[CindyH]

Lovely answer to a newbie - don't say "yuck you're doing it wrong", say "here's the answer to your question and a bonus improvement". Well done!