Tutorial of Unix Commands Professor: Dr. Shu-Ching Chen TA: Samira Pouyanfar/Hector Cen Spring 2018

Outline Introduction How to log in to the servers? How to transfer files between your computer and the server? Unix basic commands

Outline Introduction How to log in to the servers? How to transfer files between your computer and the server? Unix basic commands

What is UNIX? UNIX is an operating system which was first developed in the 1960s It is a stable, multi-user, multi-tasking system for servers, desktops and laptops There are many different versions of UNIX (or based in UNIX): Sun Solaris GNU/Linux MacOS X

The UNIX Operating System Everything in UNIX is either a file or a process A process is an executing program identified by a unique PID (process identifier) A file is a collection of data. They are created by users using text editors, running compilers etc.

The Directory Structure The full path to the file report.doc:   "/home/its/ug1/ee51vn/report.doc" All the files are grouped together in the directory structure The file-system is arranged in a hierarchical structure, like an inverted tree. The top of the hierarchy is traditionally called root (written as a slash / ) In the diagram above, we see that the home directory of the undergraduate student "ee51vn" contains two sub-directories (docs and pics) and a file called report.doc.  The full path to the file report.doc is "/home/its/ug1/ee51vn/report.doc"

Outline Introduction How to log in to the servers? How to transfer files between your computer and the server? Unix basic commands

How to log in - Windows Download putty (SSH client) from http://www.chiark.greenend.org.uk/~sgtatham/putty/ latest.html PuTTY is a free implementation of Telnet and SSH for Windows and Unix platforms

Connect to the server The host is margay.cs.fiu.edu 1 2 3 4

Log in - Account information Login as : Your FIU username Password : Your first initial + PantherID + Your last initial For example, Steven Jackson with PID 1234567 should have password s1234567j (if you haven’t already changed it)

How to log in - Macos Use the existing SSH client in macOS through Terminal by following the steps: - Search for Terminal from Spotlight, e.g., located on the upper right corner of your screen (or press Command+SpaceBar) - Open Terminal - Connect to the server margay.cs.fiu.edu using the following command: ssh your_FIU_user@margay.cs.fiu.edu - Type your password - Now, you are connected.

How to log in - Macos

Outline Introduction How to log in to the servers? How to transfer files between your computer and the server? Unix basic commands

Transfer files to and from the server You have several options: For Unix-like environments: scp command (secure copy) sftp (through Cyberduck application) For Windows environments: sftp (FTP through SSH) (Filezilla)

Transfer files to and from the server Using scp: Syntax: scp file username@hostname:/destination/folder scp username@hostname:/src/file dest Example: $ scp Project1.docx jdoe001@margay.cs.fiu.edu:/home/bear-b/users/jdoe001 It will copy the file Project1.docx from the local computer to the remote computer and store it in /home/bear-b/users/jdoe001 $ scp jdoe001@margay.cs.fiu.edu:/home/bear-b/users/jdoe001/script.sh Project1/ It will copy the file script.sh from the remote computer to the local computer and store it in Project1 folder

Transfer files to and from the server Using FileZilla (Windows): - Credentials

Transfer files to and from the server Using FileZilla (Windows): - Accept unknown host’s key

Transfer files to and from the server Using FileZilla (Windows): - Connected

Transfer files to and from the server Using FileZilla (Windows): - To upload files to the server

Transfer files to and from the server Using FileZilla (Windows): - File is uploaded to the server

Transfer files to and from the server Using FileZilla (Windows): - To download files from the server

Transfer files to and from the server Using FileZilla (Windows): - File is downloaded from the server

Transfer files to and from the server Using Cyberduck (macOS): - Credentials

Transfer files to and from the server Using Cyberduck (macOS): - Connected

Transfer files to and from the server Using Cyberduck (macOS): - To upload files to the server

Transfer files to and from the server Using Cyberduck (macOS): - File is uploaded to the server

Transfer files to and from the server Using Cyberduck (macOS): - To download files from the server

Outline Introduction How to log in to the servers? How to transfer files between your computer and the server? Unix basic commands

Commands about Files (1) ls : list the contents of your current directory. Format Options -a : list all the files including the hidden ones -l : list not only the filenames but also the related info -t : list content sorted by modification time (newest first) ls [option] [directory][file]

Commands about Files (2) ls : list the contents of your current directory. Format ~ (your home directory) Example: List all the files in your Documents folder ls ~/Documents/ ls [option] [directory] [file] Home directory Documents Desktop Downloads / …

Commands about Files (3) File permission Example: ls –l Field1 : A set of nine permission flags Field2 : link count Field3 : owner of the file Field4 : group of the file Field5 : size in bytes Field 6-8 : Last modification date Field9 : file/folder name

Commands about Files (4) chmod : change the permission flags of the files Format Examples chmod g+w myfile chmod g-rw myfile chmod –R g+rw myfile chmod [option] [types][+/-][types of permission] filename Who: u=user, g=group, o=other, a=all (default) Opcode: + means add permission - means remove permission = means assign permission and remove the permission of unspecified fields Permission r=Read, w=write, x=Execute

Example The sticky bit S should have always been called the "restricted deletion bit" given that's what it really connotes. When this mode bit is enabled, it makes a directory such that users can only delete files & directories within it that they are the owners of.

Commands about Files (5) pwd : print out the current working directory cd : change directory cd . (.) means the current directory C (..) means the parent of current directory Cd cd with no argument will return you to your home directory cd . cd .. cd Use the commands cd, ls and pwd to explore the file system.

Commands about Files (6) cp : copy files Format Options -i : It can be used to avoid overwriting the original file -r : Copy the folder and all the files and subfolders under it. cp [options] File1 File2

Commands about Files (7) scp : securely transfer files between two Unix computers To: From: scp [options] username1@source_host:directory1/File1 local_dest scp [options] local_file username1@source_host:/destination

Commands about Files (8) mv : move a file from one place to another or rename a file. Format mv File1 File2 *.txt : all the files ended with .txt

Commands about Files (9) mkdir : create a directory Format rm : remove files or directories Option -i : ask before actually delete -r : delete the folders and all the files and subfolders under it mkdir directory_name rm [option] file1 file2 file3…

Commands about Files (10) test : A command in Unix that evaluates conditional expressions. Format or The functions will return true if the object exist or the condition specified is true. File functions -d Filename : Filename is a directory -s Filename : Filename has a size greater than 0 -f Filename : Filename is a regular file test expression [ expression ] echo: print a message. It's a handy way to create customized output in your terminal

Commands about File’s contents (1) cat : display the contents of a file on the screen Format head : display the first ten lines of a file to the screen tail : display the last ten lines of a file to the screen cat file1 head –n file1 tail –n file1

Commands about File’s contents (2) wc : word count Format Options -w : find out how many words the file has -l : find out how many lines the file has -m: find out how many characters the file has wc [options] file

Commands about File’s contents (3) grep : It searches files for the specified words or patterns. Format: Options: -c : Display the number of columns which satisfied the pattern. -i : Ignore case distinctions in both the PATTERN and the input files. -v : Invert the sense of matching, to select non-matching lines. grep [options] [pattern] file

Pipe: It treats the output the execution of one command as the input of the next command A | B | C

Commands about Text processing (1) cut : extract sections from each line of a file. Format Option -c : character -f : field -d “:” : delimiter (default is a tab) cut [options] [range] filename

Commands about Text processing (2) Range N-M N- -M cut [options] [range] filename

Commands about Text processing (3) awk: It is a text processing utility on Linux based operating systems. It provides an scripting language of its own. Format: Options: -F : specify the file separator -f : specify the file that will be processed. -v var=val : Assigns a value to a variable before execution of the program begins awk [options] [script] file

Commands about Text processing (4) awk examples: Print the first column of the file latlonpts.txt, specifying the delimiter as ‘,’

Commands about Text processing (5) awk examples: Assign main bulding as the value of the variable pattern. It can be later used to perform operations on text.

Commands about Text processing (6) sort : sort lines of a text file or files Default : sort without any option will sort the file alphabetically Format uniq : remove duplicate adjacent lines from sorted file. sort [option] file

Redirection & Pipes (>, >>, <, |) These are operators that allows us to control and/or redirect the commands output. We will focus on the following: >: Directs the output of the command to a file. >>: Appends or create the output of the command to a file. Creates the file if it doesn’t exist, otherwise appends to it. <: Takes input for a command. |: The pipe operator. It passes the output of one command as the input of another.

Redirection & Pipes (>) Example: To send the output of a command to a file. It sent the output of the command date to a file called today.txt. It creates the file if it doesn’t exist, otherwise overwrites it.

Redirection & Pipes (>>) Example: To append the output of a command to a file. It sent the output of the command who to the end of the file called today.txt. It creates the file if it doesn’t exist.

Redirection & Pipes (<) Example: To take input for a command. It took the contents of the file latlonpts.txt as input for the wc command.

Redirection & Pipes (|) Example: To take input for a command. Dumps the contents of the file sample.txt, which is then piped to the program grep and finally piped as input for the wc program. It can be seen as: command1 | command2 | command3

Commands about Text processing (7) sed: stream editor Detailed tutorial : http://www.grymoire.com/Unix/Sed.html Important function -> Substitution Format : sed 's/term1/term2/g‘ filename

Unix Tutorials for Beginners http://www.ee.surrey.ac.uk/Teaching/Unix/unixin tro.html http://people.ischool.berkeley.edu/~kevin/unix- tutorial/toc.html https://users.cs.duke.edu/~alvy/courses/unixtut/