LINUX Viewing text files from the shell prompt

The head Command

head <filename>
By default, you can only read the first ten lines of a file.You can change the 
number of lines displayed by specifying a number option. 

head -20 <filename>

The tail Command 

The reverse of head is tail. Using tail, you can view the last ten lines of a file. This can be useful for viewing the last ten lines of a log file for important system messages. You can also use tail to watch log files as they are updated. Using the -f option, tail automatically prints new messages from an open file to the screen in real-time. For example, to actively watch /var/log/messages, enter the folowing at a shell prompt (as the root user):  
tail -f /var/log/messages
Press[Ctrl]-[C] when you are finished. 



Viewing Files with less



The format of the less command is:


less <filename>

The main difference between more and
 less is that less allows
 backward and single-line movement using the same navigation as
 man pages: press the [Space] bar to go down one
 page, the [B] to go back one page, the
 directional (or "arrow") keys to move one line at a
 time, and [Q] to quit.

To search the output of a text file using
 less, press [/] and
 enter the keyword to search for within the file.


/stuff
































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