



                Searching:  
                
                I have a set of lines....
                
                I get these line by: 
                
                cat a file
                ls a dir
                etc.
                
                and I want to search in these lines:
                
                I have command named grep 
                
                $ grep '...'  file
                        ^ what to search for
                        
                this Pattern is a Regular Expression
                
                
                abc <- a string of chars
                x*  <- the '*' means: Zero of more of the char to the left
                .   <- the '.' means any single char   
                [ ] <- the [ ]  provide a choice of char
                ^   < the '^' means the start of the line
                $   <- the '$' means the end of the line
                
                        
                ---------------------------------------------
                
                I now want to search for files, by:
                name
                size
                permission
                access time
                owner
                etc
                
                 action include:
                delete
                exec (a command)
                print (the default)
                etc


                I have a find command
                
           $ find <the dir to start searching> <the search rules> <what action to take when found>
           
           $ find /home -name 'states' -print
           
           -----------------------------------
           Shell side step
           in the Shell I can redirect the output to a file using '>'
           
           $ find /home -name 'states' -print  > results.txt
           
           in the Shel I can redirect error message using '2>' 
           
           $ find /home -name 'states' -print > results.txt 2> /dev/null
           
           -------------------------------------
           
            find "tests" can search by:
            
            name
            owner
            permission
            size
            etc
            
            action include:
            delete
            exec (a command)
            print (the default)
            etc
