SIMPLE UNIX COMMANDS

1) File and Directory Manipulation

cat f1		:PRINT the contents of the file "f1" on the screen
cd d1		:CHANGE DIRECTORY to "d1" (make "d1" your CURRENT DIRECTORY)
cp f1 f2	:COPY file "f1" to file "f2"
diff f1 f2	:PRINT the DIFFERENCES between files "f1" and "f2"
file fname	:describe what kind of file FNAME is
grep pat f1	:PRINT all lines in f1 which have the pattern "pat" on them.
head -n f1	:PRINT the first n lines of "f1" on the screen
ls		:LIST contents of the current working directory
mkdir d1	:CREATE the directory d1
more f1		:PRINT the contents of file "f1" a screenful at a time
mv f1 f2	:MOVE file "f1" to file "f2" (i.e. RENAME file "f1" "f2")
pwd		:print the CURRENT DIRECTORY
rm f1 f2 f3	:REMOVE files f1, f2, and f3.
rmdir d1	:REMOVE the directory d1
tail -n f1	:PRINT the last n lines of "f1" on the screen
vi f1		:EDIT file "f1" (CREATES "f1" if it does not exist)

2) Compiling programs

f77 -o p1 p1.f	:compile the FORTRAN file "p1.f" and put the output in "p1"
cc -o p1 p1.c	:compile the C file "p1.c" and put the output in "p1"
error		:interpret COMPILER ERRORS and put them in the source file
make		:a program which makes it easy to COMPILE programs
p1		:RUN the program p1 which you just compiled via f77 or cc.

3) Keeping Track of Disk Usage
df		:tell how much disk space is left on the computer
du		:tell how much disk space is being used by the current
		 working directory
du dirname	:tell how much disk space is being used by the directory
		 "dirname"

4) Keeping Track of Jobs; Job Control

ps		:PRINT all the PROCESSES you have running
jobs		:PRINT all the JOBS you have running
<ctrl-Z>	:suspend the current job
bg		:put the most recently suspended job in background
command &	:the & means to run the job in background and frees the
		 terminal so you can go on to something else while the job
		 is running.
fg		:bring a job into the foreground
%2		:bring job number 2 to foreground (2 is the number next to the
		 job when you use the "jobs" command.
kill %3		:kill job number 2
kill 2365	:kill process number 2356.  (2356 is the number next to the
		 process when you use the "ps" command.

Communicating with Other Users

mail ralph	:send mail to the user whose login name is ralph
write ralph	:write a message to the user whose login name is ralph

Logging on and Off

login		:This is the login prompt.  First type your user name, then
		 your password.
logout		:log out of the system.
passwd		:change your password

Printing Files to the Line Printer

lpr filename	:send the file "filename" to the line printer
print filename	:send the file "filename" to the line printer with a header
cancel		:cancel a line printer job

Getting Documentation

apropos word	:PRINT an INDEX of all programs which pertain to "word"
man -k word	:same as apropos
man progname	:PRINT the MANUAL ENTRY for the program named "progname"

Clearing the Screen

clear		:clear the terminal screen but not the graphics

Machine to Machine File Transfer and Communications
kermit		:KERMIT intra-machine FILE TRANSFER program
ftp		:network file transfer program
rsh		:remote shell on another computer
rlogin		:log in to a remote computer
telnet		:log in to a remote computer

Command Interpreters and Environment
csh		:the C shell
sh		:the Borne shell
ksh		:the Korn shell
tset		:set terminal capabilities
stty		:set terminal parameters

Miscellaneous
remind		:print daily reminder memos

CONCEPTS
directory structure
file permissions
shell environments
shell scripts
environment variables
pipes/redirects
standard input, standard output, standard error