Chapter 1-17 Commands:

Commands:

Command Description Examples
!! re-executes the last command in C shell  
!$ repeat the last argument from the previous command  
!* repeat all arguments of the previous command  
!n:p allows you to see a command but not execute it.  
!number repeats a specific number command  
alias The alias and unalias utilities create or remove a pseudonym or shorthand term for a command or series of commands. Change copy (cp) to include a confirmation prompt before overwritting a file:
alias cp="cp -i"
cal The cal utility writes a Gregorian calendar to standard output. $ cal
$ cal 2000
$ cal 9 2005
cancel The cancel utility cancels print requests $ cancel printer1-203
request "printer1-203" cancelled

$ cancel -u <username>

cat Concatenate and display files $ cat dante
The Life and Times of Dante
by Dante Pocai

Mention "Alighieri" and few may know about whom you are talking. Say "Dante," instead, and the whole world knows whom you mean. For Dante Alighieri, like Raphael
$

cd The cd utility will change the working directory of the current shell execution environment $ cd

$ cd ..

$ cd /home/user2/dir1

$ cd ./dir1

chmod Change File or Directory Permissions Deny execute permission to everyone:
$ chmod a-x filename

Allow only read permission to everyone:
$ chmod 444 file1

Make a file readable and writable by the group and others:
$ chmod go+rw file2

compress The compress utility will attempt to reduce the size of the named files. -v, -f

$ compress -vf file
file: compression 37% -- replaced with file.Z

cp Copies files -i, -r

$ cp ~/home/* /tmp

$ cp -i ~/home/user2/* /bkup

$ cp -ri ~/home/user2/* /bkup
diff The diff utility will compare the contents of 2 files and write to standard output a list of changes necessary to convert the first file into the second file.  No output will be produced if the files are identical. $ diff -c fruit fruit2
*** fruit Fri May 8 11:32:49 1998
--- fruit2 Fri May 8 14:55:21 1998
***********
***2, 8****
orange
apple
banana
-pear
-mango
tomato
pomegranate
---2, 8-----
orange
apple
banana
tomato
+guava
+mango
pomegranate
ENV Variable used in conjunction with personalizing the login environment ENV=$HOME/.kshrc; export ENV
file Determines file type $ file dante
dante:    English text

$ file beans
beans:    Frame Maker Document

$ file da* fi*
dante:      English Text
dante_1:    English Text
file1:      English Text
file2:      ascii text
files.jar:  java program
files.tar:  USTAR tar archive 
find The find utility recursively descends the directory hierarchy for each path seeking files that match a Boolean expression. -o

$ find /home/user2 -name 'dir*'
/home/user2/dir2
/home/user2/dir3

ftp The ftp (File Transfer Protocol) application is part of the TCP/IP protocol suite and is standard with the UNIX operating system. It can be used to transfer files using ASCII or binary mode between systems using similar or dissimilar operating systems. $ ftp venus
Connected to 129.150.212.16.
220 venus FTP server (UNIX(r) System V Release 4.0) ready.
Name (129.150.212.16:lister): Return <CR>
331 Password required for lister.
Password: xxx
230 User lister logged in.
ftp> cd /etc/inet
250 CWD command successful.
ftp> bin
200 Type set to I.
ftp> get hosts /tmp/hosts
200 PORT command successful.
150 Binary data connection for hosts (129.159.129.38,33425)
(77 bytes)
226 Transfer complete.
local: /tmp/hosts remote: hosts
77 bytes received in 0.0014 seconds (5,25 Kbytes/s)
ftp> bye
grep Searches a file for a pattern. -i

$ grep banana ./*
/home/user2/fruit: banana
/home/user2/fruit.tar:banana
/home/user2/fruit2: banana
/home/user2/fruit2.tar:banana
groups displays all the groups a user is a member of. $ groups user1 user2
user1 : staff
user2 : staff
head Displays the first few lines of files. $ head -5 /usr/dict/words
1st
2nd
3rd
4th
5th
$
history This utility lists or edits and re-executes commands previously entered into an interactive shell. $ history
339 man grep
340 pwd
341 grep banana ./*
342 history
$ r 340
pwd
/home/user2
$
id Returns the user identity. -a

$ id
uid=1002(user2) gid=10(staff)

$ id -a
uid=1002(user2) gid=10(staff) groups=10(staff)
init 0 Its primary role is to create processes from information stored in the file /etc/inittab. 

At any given time, the system is in one of eight possible run levels.  A run level is a software configuration under which only a selected group of processes exist.  Run levels 0, 5, 6 are reserved states for shutting the system down.

 

 

jar Combines backup and compress into one tool. c,t,x, f, v

$ jar cvf bundle.jar *
adding 0.au
adding 1.au
adding 2.au
adding 3.au
$
kill The kill utility sends a signal to the process or processes specified by each pid operand. -9

$ kill -9 100 -165
$ kill -s kill 100 -165
lp lp submits print requests to a destination. -d, -o, -n, -m

$ lp ~/fruit2
request id is printer1-203 (1 file(s))
lpsched The lpsched command starts or restarts the LP print service  
lpstat lpstat displays information about the current status of the LP print service to standard output $ lpstat printer1
printer1-106  root   587 Mar 22 16:06 on printer1
printer1-107  user2   85 Mar 22 16:10 on printer1
$
ls For each file that is a directory, ls lists the contents of the directory; for each file that is an ordinary file, ls repeats its name and any other information requested. -a,-F,-l,-lt,-ld,-E

$ ls
dante   dir1   dir3

$ ls -l
-rwxr-xr-x  1  user2  staff  110 Apr 19  dante
drwxr-xr-x  5  user2  staff  110 Apr 19  dir1
drwxr-xr-x  4  user2  staff  110 Apr 19  dir3

mailx Interactive message processing system. $ mailx user2@cisco.com < dante.doc
man The man command displays information from the reference manuals. It displays complete manual pages that you select by name, or one-line summaries if selected by keyword -s, -k

$ man man

$ man cd

mkdir The mkdir command creates the named directories in mode 777 (possibly altered by the file mode creation mask umask(1)). $ mkdir Reports
$ ls -dl Reports
drwxr-xr-x 2 user2 staff 512 Jan 28 16:24 Reports

$ mkdir -p practice/dir1/admin
$ ls -R practice
practice:
dir1 mailbox project research
practice/dir1:
admin
practice/dir1/admin:
more The more utility is a filter that displays the contents of a text file on the terminal, one screen at a time.  It normally pauses after each full screen. $ cat dante | more
mv Moves files -i

$ mv file1 file_april30

$ mv file1 /home/user2/bkup
noclobber Command which prevents the overwriting of files during redirection $ set -o noclobber
$ cat fruit > fruit2
/bin/ksh: fruit2: file already exists
passwd Changes login password and password attributes $ passwd
passwd:  Changing password for user2
Enter login password:  abc123
New password:  unix123
Re-enter new password:  unix123
passwd (SYSTEM): passwd successfully changed for user2
$
pgrep The pgrep utility examines the active processes on the system and reports the process Ids of the processes whose attributes match the criteria specified on the command line. Obtain the process ID of sendmail:

$ pgrep -x -u root sendmail
283

ping The ping command tests basic connectivity between TCP/IP hosts by sending an ICMP (Internet Control Message Protocol) echo request to another computer or "host" on a TCP/IP network. If there is a reply from the destination host, then there is a good connection between them. $ ping jupiter
jupiter is alive

$ ping 192.13.145.10
192.13.145.10 is alive

pkill searches for the process to kill Terminate the most recently created xterm:

$ pkill -n xterm

ps The ps command prints information about active processes. -e, -f, -u

$ ps

PS1 A variable which can be changed by the user to alter the appearance of the default shell prompt. $ PS1="new prompt$ "

$ PS1="$PWD $ "

pwd pwd writes an absolute path name of the current working directory to standard output $ pwd
/home/user2/dir1
rlogin Use the rlogin command to establish a remote login session on another workstation. $ rlogin saturn
Password:
Last login: Mon Dec 21 11:04:27 from venus
Sun Microsystems Inc. SunOS 5.7 Generic October 1998
$
shutdown By default, shutdown brings the system to a state where only the console has access to the operating system. This state is called single-user.  
sleep The sleep utility will suspend execution for at least the integral number of seconds specified in the time operand $ sleep 60&
r Repeats a command from the history list. 170 pwd
171 ls
172 cd ~

$ r 170

rm Remove directory entries -i,-r

$ rm -r dir1

set + o vi Turns command line editing on.  
set - o vi Turns command line editing off.  
set prompt Sets the default shell prompt in a C shell. % set prompt="hello %"
sort The sort command sorts lines of all the named files together and writes the result on the standard output. $ sort file1

$ sort +1n file2

strings Finds printable strings in an object or binary file $ strings /usr/bin/cat
SUNW_OST_OSCMD
usvtebn
usage: cat [ -usvtebn ] [-|file] ...
cat: Cannot stat stdout
cat: cannot open %s
cat: cannot stat %s
cat: input/output files '%s' identical
cat: close error
<some output omitted>
su Allows a user to become super user or another user - username

$ su -student6
Password:
$
tail Displays the last few lines of files. $ tail -5 /usr/dict/words
zounds
z's
zucchini
Zurich
zygote
$
tar The tar command archives and extracts files to and from a single file called a tarfile. c,t,x, f, v

$ tar cvf backup.tar /home/user2/*

telnet Telnet is another good network troubleshooting tool. It is a non-graphical communications utility that can be used to check the upper layers of the OSI model. $ telnet beach
Trying 192.168.49.10 ...
Connected to beach
Escape character is '^]'.
4.2 BSD UNIX (beach)
login: jdupont
Password:
Last login: Wed Jun 1 19:03:33 on console
beach% (Enter commands)
beach% exit
Connection closed by foreign host
$
touch The touch utility sets the access and modification times of each file.  The file is created if it does not already exist $ cd ~/practice

$ touch mailbox project research

$ ls
mailbox project research

unalias The alias and unalias utilities create or remove a pseudonym or shorthand term for a command or series of commands. $ alias cp="cp -i"
$ unalias cp
uncompress The uncompress utility will return a previously compressed file back to its original size -v

$ uncompress -vf file.Z

unset history Turns history tracking off.  
vi editor Command Mode Initial default mode for creating and editing files, cursor positioning and modification of existing text. All commands are initiated from this mode. Pressing Esc from either of the other modes will return you to command mode.  
vi editor Entry Mode Used for entry of new text. Entering an insert command such i (insert), a (append) and o (open new line) will take you from command mode to entry mode. Pressing escape (Esc) returns to command mode. Entry commands are entered by themselves without pressing the Enter key. a, i, o, A, I, O
vi editor Last Line Mode Used for saving your work and quitting vi. Type a colon (:) to get to this mode. Pressing the Enter key to returns to command mode. :w, :wq, ZZ, :q!, :wq!
wc The wc utility reads one or more input files and, by default, writes the number of newline characters, words, and bytes contained in each input file to the standard output. $ wc dante
33 223 1320 dante

$ wc -l dante
33 dante

whatis whatis looks up a given command and displays the header line from the manual section $ whatis cd
cd    cd (1)   -change working directory
who Lists who is on the system. 0H,-q

$ who
user2 console  Apr 30 12:37   (:0)
user2 pts/4    Apr 30 12:40   (:0.0)
$

whoami Displays the effective current username $ whoami
user2
who am i Displays the effective current username. $ who am i
user2 pts/4    Apr 30 12:40   (:0.0)