11 Advanced Linux ‘Grep’ Commands on Character Classes and Bracket Expressions
Jalpan Trivedi
If you will divide the word grep like g/re/p then the meaning of grep is (globally search a regular expression and print) which search pattern from the file and print the line on the screen i.e. standard output. Search Alpha Characters Similar options like if you want to search line which will start from only [A-Z & a-z] i.e. Alpha Characters . Search Blank Characters Another options like if you want to search line which will start from [Tab & Space] i.e. Blank Characters. Search Digit Characters The digit option for grep is also very useful to search line which will start from digit [0-9] i.e. Digit Characters. $ grep ^[[:xdigit:]] tecmint.txt I have explained the advanced functionality of grep which is very strong and powerful tool to search the pattern in a File.