Regex: ignore case sensitivity

Question

How can I make the following regex ignore case sensitivity? It should match all the correct characters but ignore whether they are lower or uppercase.

G[a-b]         


        

Answer 1

Addition to the already-accepted answers:

Grep usage:

Note that for greping it is simply the addition of the -i modifier. Ex: grep -rni regular_expression to search for this 'regular_expression' 'r'ecursively, case 'i'nsensitive, showing line 'n'umbers in the result.

Also, here's a great tool for verifying regular expressions: https://regex101.com/

Ex: See the expression and Explanation in this image.

References:

• man pages (man grep)
• http://droptips.com/using-grep-and-ignoring-case-case-insensitive-grep