Transcript Basic Unix Commands
Some basic Unix commands
Understand the concept of loggin into and out of a Unix shell Interact with the system in a basic way through keyboard and terminal window Create, copy and delete files, edit files Understand and use commands like: ls cd mv cp rm cat date mkdir rmdir Be able to navigate up and down in the file system 1
Logging in and out
As a Unix user you can log in and out When loggin in, the system checks your user name and password – if correct, the system starts a shell for you and places you in the starting directory The shell runs as your process until you log out The shell gives you a prompt and interprets what you type 2
Interacting with the system
Default input from the keyboard Default output to the terminal window When hitting
return
the shell interprets what you have typed The shell finds a command with that name and starts a process to execute the command During this time the shell process sleeps and wakes up when the command process is done 3
Working with files
Creating files – Can use vi or any editor – Can use cat with input and output redirection Copying files – – cp makes a copy of an existing file cat can do it also, we practice this to understand I/O redirection Deleting files: rm Editing files we will learn about vi , the most available Unix editor other editors are available on the system as applications 4
More important commands
ls lists the files in the current directory by name cd changes your position in the directory tree mv moves a file from one directory to another rm deletes a file date prints the current date and time mkdir creates a directory rmdir deletes a directory (must be empty) All Unix commands have options 5
Navigating in the directory tree
The cd command changes your position in the directory tree, destination is parameter, it must be the name of a directory visible in the current directory – cd without parameter – Relative movement (relative pathname) – Absolute movement (absolute pathname) – cd ..
and cd .
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To Make a Good Password
A good password – Easily remembered by YOU – Difficult to be guessed by others Tricks to make a good password – Pick letters from a sentence I l o v e U n i x Ioenx – Pick letters, numbers, and symbols that sound, look like, or replace a phrase I hate carrots !
i h8 ^s !
A bad password not only harms you – Attacks are much easier with a compromised account on a computer 7
Some Basic Commands
who: Who are using the system.
terra$ who katchab ttyp0 scott jenny tty02 tty03 Aug 11 08:47 Aug 10 11:01 Aug 10 07:21 who am i: Who am I.
terra$ who am i katchab ttyp0 Aug 11 08:47 8
Some Basic Commands
ls: List the files under current directory terra$ ls readme cs211.2.ppt cs211.ppt.gz notes.zip cs211.1.ppt cs211.3.ppt make/ shell/ cat: Display the content of a file terra$ cat readme Unix is easy!
terra$ 9
Some Basic Commands
Ctrl-c: (press
terra$ cat ^c terra$ netscape: surf the net. ONLY WHEN X is running terra$ netscape lynx: surf the net.
terra$ lynx www.yahoo.com
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Some Basic Commands
man: See the manual page of a command.
terra$ man cat Reformatting page. Wait... Done User Commands cat(1) NAME cat - concatenate and display files SYNOPSIS cat [ -nbsuvet ] [ file ... ] DESCRIPTION cat reads each file in sequence and writes it on the stan dard output. Thus: example% cat file prints file on your terminal, and: example% cat file1 file2 >file3 concatenates file1 and file2, and writes the results in file3. If no input file is given, cat reads from the stan dard input file.
OPTIONS--More--(11%) 11
Commands covered today
File Manipulation Commands: – copy (cp), rename (mv), print (lpr), examine a file (head, more, cat), search a file (grep), delete (rm) Miscellaneous commands – echo, date, cat Basic File Compression – gzip, gunzip Finding Utilities and help – which, whereis, apropos, man, info Communicating online – Chat (write/talk) and email (pine) 12
Communication Utilities in UNIX
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The talk Command
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A Complete talk Session
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A Complete talk Session
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A Complete talk Session
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The write Command
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E-Mail Programs
Some Programs available in Unix/Linux – Mail – most basic, low level mail command – ELM – PINE (PINE Is Not Elm), more user friendly text mail – Outlook, GUI driven – Eudora – Netscape Mailer 19
Email Address
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PINE
A menu-driven client Uses pico as an editor Allows MIME attachments Main Menu – C - Compose to write a message – I or L - View messages – Q - Quit 21
Local login
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Remote Login
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