Introduction to Unix/Linux

ICN Summer InstituteJackson State University

June 16, 2009

Mississippi Center for Supercomputing Research

Jason Hale & Susan Lukose, Ph.D.

Unix is an Operating System

An O/S manages access to the resources of a computer.

O/S host applications, shielding them from the hardware.

Other popular operating systems:Windows XP, Windows Vista, MAC OS X

Unix looks more like DOS than Windows

Common Flavors of UnixIBM’s AIX

Hewlett Packard’s HP-UX.

Sun’s Solaris

SGI’s IRIX

Apple’s MAC OS X

Unix Variants: Linux, BSD, …

Why Learn Unix/Linux?

Unix/Linux commonly used on computer “servers”:Web serversDatabase serversSupercomputers/Clusters

Over 50% of servers in corporations run Unix or Linux

A little Unix experience goes a long way, on the job, and looking for a job

Why Learn Unix/Linux?

At UM/MCSR:TO RUN COMPUTATIONAL CHEM APPS!SAS is installed on UM’s Research Server: willow

- more disk space than on your PC’s- run one calculation for several days

Matlab is installed on willow.Mathematica on mimosa cluster

for calculations too big for your PC or MAC

Student programming assignments may be completed on MCSR/UM systems

Distributions of Linux

• Red Hat Enterprise Linux• Fedora• SUSE Linux Enterprise• openSUSE• Debian GNU/Linux• Ubuntu• Mandriva Linux• Slackware Linux • Gentoo

Components of Unix

Shells Kernel

Shells

System Utilities

End-UserUtilities

Developmenttools

Docs

Commands

MCSR Unix Workshops Will Cover:

Shells Kernel

Shells

System Utilities

End-UserUtilities

Developmenttools

Docs

Commands

Unix/Linux File System

Similar to MS/DOS Files (Windows Command Prompt):

Differences

Windows LinuxCase doesn’t matter Case sensitiveSpaces ok in filenames Spaces not OK in namesBackslash used in pathnames Forward slash in pathsUser “Administrator” User “root”

jsujsu

tracct1tracct1 tracct2tracct2 r1311r1311

Unix/Linux File Permissions

Unix/Linux File Permissions