GREP Command

Grep command is used for searching strings in a file or files present in directory and subdirectory

Examples of Grep Command

Search for a string ‘abc’ in filename.txt

Grep abc filename.txt

Search for a string ‘abc’ in all files in current directory

Grep abc *

Search for a string ‘abc’ in files of current directories and subdirectories

Grep -r abc *

Search for entire pattern “abcd” in a file aks.txt

Grep -w “abcd” aks.txt

Search string with ignoring cases

Grep -i abc filename.txt

To count the number of lines where matching string “abcd” is found in filename.txt

Grep -c abc filename.txt

Show the lines where matching string ‘abc’ is not found in filename.txt

Grep -v abc filename.txt

To search more than one word use egrep

Egrep -w ‘first_word|2nd_word’ filename.txt

To display output of grep in color

Grep – – color abc filename.txt



Option Description

-b            –Show the block number at the beginning of each line.

-c            –Show the number of matched lines.

-h            –Show the matched lines, but do not Show the filenames.

-i             –Ignore case sensitivity.

-l             –Show the filenames, but do not Show the matched lines.

-n            –Show the matched lines and their line numbers.

-s            –Silent mode.

-v            –Show all lines that do NOT match.

-w           –Match whole word.