Regular expressions (regex) are extremely useful in extracting information from any text by searching for one or more matches of a specific search pattern. The basic anchors - ^ and $ expression action ^The matches any string that starts with The end$ matches a string that ends with end ^The end$ exact string match (starts and ends with The end) pragmatic matches any string that has the text pragmatic in it   The basic quantifiers — * + ? and...

This page shows a growing list of common commands for viewing and managing your Centos server. ls syntax $ ls [options] [file|dir] ls command main options: ls -a list all files including hidden file starting with '.' ls --color colored list [=always/never/auto] ls -d list directories - with ' */' ls -F add one char of */=>@| to enteries ls -i list file's inode index number ls -l list with long format - show permissions ls -la list long format including hidden files ls...