COMMAND DESCRIPTION
#passwd Change user password
#pwd Print current directory
#cd Change directory
#ls List of files in a directory
wildcards * matches any number of characters, ? matches a single character
#file Print the type of file
#cat Display the contents of a file
#pr Display the contents of a file
#pg or page Display the contents of a file one page at a time
#more Display the contents of a file one page at a time
#clear Clear the screen
#cp or copy Copy a file
#chown Change the owner of a file
#chgrp Change the group of a file
#chmod Change file modes, permissions
#rm Remove a file from the system
#mv Rename a file
#mkdir Create a directory
#rmdir Remove a directory
#grep Pattern matching
#egrep grep command for extended regular expressions
#find Used to locate files and directories
#>> Append to the end of a file
#> Redirect, create, or overwrite a file
#| Pipe, used to string commands together
#|| Logical OR—command1 || command2—execute command2 if command1 fails
#& Execute in background
#&& Logical AND—command1 && command2—execute command2 if command1 succeeds
#date Display the system date and time
#echo Write strings to standard output
#sleep Execution halts for the specified number of seconds
#wc Count the number of words, lines, and characters in a file
#head View the top of a file
#tail View the end of a file
#diff Compare two files
#sdiff Compare two files side by side (requires 132-character display)
#spell Spell checker
#lp, lpr, enq, qprt Print a file
#lpstat Status of system print queues
#enable Enable, or start, a print queue
#disable Disable, or stop, a print queue
#cal Display a calendar
#who Display information about users on the system
#w Extended who command
#whoami Display $LOGNAME or $USER environment parameter
#who am I Display login name, terminal, login date/time, and where logged in
#f, finger Information about logged-in users including the users .plan and .project
#talk Two users have a split screen conversation
#write Display a message on a user’s screen
#wall Display a message on all logged-in users’ screens
#rwall Display a message to all users on a remote host
#rsh or remsh Execute a command, or log in, on a remote host
#df Filesystems statistics
#ps Information on currently running processes
#netstat Show network status
#vmstat Show virtual memory status
#iostat Show input/output status
#uname Name of the current operating system, as well as machine information
#sar System activity report
#basename Base filename of a string parameter
#man Display the on-line reference manual
#su Switch to another user, also known as super-user
#cut Write out selected characters
#awk Programming language to parse characters
#sed Programming language for character substitution
#vi Start the vi editor
#emacs Start the emacs editor
Sample from seshu
Take from field for fix length file.
#cut -c 40-50 File.dat > xx28cv24.txt
