ln - make a link to a file
Format
ln [option] existing-file new-link
Summary
Creates a hard link to the file specified by existing-file with the name given by the new-link argument. A hard link to a file is indistinguishable from the original. A hard link has to be on the same filesystem as the original file. A symbolic link may be across filesystems and existing file and new-link may be directories as well as files.
Options
-s creates a symbolic link instead
locate - locates files
Format
locate pattern
Summary
Lists all files in filedatabase that match the given pattern.
This utility depends on a database file with al list of all files on your filesystem. Use the updatedb utility to update your database (caution, this takes a while)
Example
#locate hepp
This search would find all files on you system that contain hepp. It would find heppgr, tghepp and tyheppl.
echo - just that... an echo :)
Format
echo [option] message
Summary
Very useful in scripting, lets you write messages to the terminal and can be used to display shell variables
Options
-n newline, prevents echo from displaying the newline at the end of the message
Example
#echo 'Hi!'
Hi!
#echo -n 'Hi!'
Hi!#
#echo $TERM <-- this is a shell variable
vt100
#
grep - search for pattern in file
Format
grep [options] pattern [file-list]
Summary
This utility searches one or more files for a pattern. The grep utility performs actions, specified by options every time
it finds a line that contains a match for the pattern.
If you use tabs or spaces in the pattern you must quote it.
Options
if you don't specify any options grep displays the line that contained a match for pattern.
-c count, causes grep to display the number of times it found a match for pattern
-i ignore case, ignores case when finding a match for pattern
-l file list, causes grep to display only the filename in which it found a match for pattern
-v reverse test, causes lines not containing a match to satisfy the search
finger - Get information about other users
Format
finger [options] [user-list]
Summary
With no arguments finger gives you a list of all users logged on to the system together with their full names, terminal device numbers the number of times they logged in and other information. If specify a user on the command line, finger gives you detailed information on that user and displays his/her .plan, .project and .forward file. The really cool thing with finger is that you can finger users on other hosts.
User list options
[user] gives you information on that user on your local system
[user]@[host] gives you information on that particular user on that particular host
@[host] lists all the users currently logged on on that host
Options
-l long, gives you detailed information on about every user currently logged on
kill - terminate a process
Format
kill [option] PID-list
Summary
Terminates all jobs with PID number=PID-list
You can determine what signal to send to terminate the process. These are the possibilities
Options
-0 sh(1) only, signals all members of process group
-9 non-catchable, non-ignorable kill (this is the one to use if you process if doesn't want to get killed)
-15 software termination signal (default)
-HUP A very useful option. This causes kill to terminate the process and to restart it afterwards.
