unix - grep basics

grep simple

# http://www.cyberciti.biz/faq/howto-search-find-file-for-text-string/

The syntax is:

grep "text string to search” directory-path

OR

grep [option] "text string to search” directory-path

OR

grep -r "text string to search” directory-path

OR

grep -r -H "text string to search” directory-path

OR

egrep -R "word-1|word-2” directory-path

OR

egrep -w -R "word-1|word-2” directory-path



$ grep "redeem reward" /home/tom/*.txt
$ grep "redeem reward" ~/*.txt
$ grep -r "redeem reward" /home/tom/
$ grep -R "redeem reward" /home/tom/
$ grep -H -r "redeem reward" /home/tom #display only file name


#to just display the file name:
$ grep -H -R vivek /etc/* | cut -d: -f1


#suppress file names
$ grep -h -R 'main()' ~/projects/*.c 

#display only words
$ grep -w -R 'getMyData()' ~/projects/ 

#search two or more words
$ egrep -w -R 'word1|word2' ~/projects/ 

#hide all errors and warnings
grep -w -R 'getMyData()' ~/projects/ 2>/dev/null

#display matched text in color
rep --color 'word' file
grep --color -R 'word' /path/to/dir
grep --color -R "192.168.1.5" /etc/
grep --color -R -h "192.168.1.5" /etc/
grep --color -R -h "192.168.1.5" /etc/ 2>/dev/null