Transcript Introduction to Database Systems

COMP1070
Lecture #4
Unix
software architecture
Correcting mistakes
System setups
Useful commands for the beginner
Commands for study
COMP1070/2002/lec4/H.Melikian
The software architecture of the UNIX operating system
COMP1070/2002/lec4/H.Melikian
UNIX Kernel

Process management
- creating, suspending, terminating and maintaining

Unix provides three primary IPC (interprocces communication)

Pipe ( resides in main memary),

Named pipe( named also as FIFO permanent communication canals
resided on the disk),

BSD Socket ( communication canals in network or on Internet)
COMP1070/2002/lec4/H.Melikian
Unix Shell
The UNIX shall is a program that start running when you log on and
interprets the commands you enter.
 UNIX shall prompt such as
$
appear in a screen when you log in and command line
follows the prompts.
$ command [[-] option(s)] [option argts] [ command argt’s]
Shell is case sensitive,
space between command, command options, option argts and
arguments
Example (listing of current directory contents)
$ ls
$ ls –la
$ ls –la f*

COMP1070/2002/lec4/H.Melikian
Correcting Mistakes
For each key combinations like <^D>- press and hald <Ctrl>key down
while pressing second key (D) down
< Back Space> or <^H>
( erase the previous character and move cursor to its position)
<^U> - erase the entire current line and move cursor to the beginning of
the line
<^C> - terminate the current command and move to next line
COMP1070/2002/lec4/H.Melikian
Some useful commands
 passwd ( yppasswd or nipasswd)

man
- man [ops][-s section] command list or
- man –k keyword_list
$ man –s2 read
To get a short description of what any particular unix command does,
you can use the whatis command.
$ whatis man
$ whatis login mkdir setenv
The whereis command allows you to search along certain path to
locate the utility programs and command such as shell programs
COMP1070/2002/lec4/H.Melikian
List of command to study and practice
Log into any UNIX machine and discover yourself the true
meaning of following commands in detail.
whoami
set
alias/unalias
hosthame
setenv
write
uname
telenet
mail
echo
passwd
elm
exit
cp
talk
login
lpr
diff
ls
ssh
more
mv
who
cat
cp
cal
uptime
COMP1070/2002/lec4/H.Melikian
Editors
Pico
Emacs
Vi
Ed
COMP1070/2002/lec4/H.Melikian
General keystroke commands and
cursor movement commands
^Shift 6 – Begin to mark a section for cutting
^C- reports coursers line and character #
^G - help
^J - justify the selected text
^K – cut out the selected text
^O- Saves, writes out the text
^R – Reads the text from file and pastes
the current position of cursor
^T - Checks Spelling
^U – Pasts the current line of text
^V -Scroll page down on the Help page
^W - Whereis ( search for character strings)
^X – Exit
^Y Scroll one page up in the Help page
COMP1070/2002/lec4/H.Melikian
^F-Move forward a ch
^B_ Move backward a ch
^P- Move previous line
^N-Move the next line
^E- Move to the end of
^V- Move to next page
^Y- Move to prev page
HW #1
Write a short description of the following UNIX
commands using man utility then send it to me.
echo , mail, talk, ps, head, wc.
Assigned 09/11/02
Due 09/14/02 by midnight
PS. To submit you have to use the fallowing command
% mail melikian < assignment.txt
Where assignment.txt is the file with your hw .
COMP1070/2002/lec4/H.Melikian