Basic Introduction to UNIX/linux

1 Basic Introduction to unix /linuxClaude Cantin Computing Support GroupInformation Management Services BranchNational Research CouncilMay 27, 20182 This page intentionally left document was produced by Claude Cantin of the National ResearchCouncil of Canada. Reproductions are permitted for non-profit purposesprovided the origin of the document is CantinNational Research Council of Canada4 History of printing:DateCopiesMarch 2003200 March 2001200 June 1999200 November 1997200 July 1996200 November 1995150 March 1995150 February 1994150 October 1993100 August 199375 February 199375 November 199235 September 199240 February 199250 December 199150 April 199150 September 199040 January 199040 Table 1: History.

2 : Berkeley System Distribution .. XENIX .. linux .. System V (formerly known as AT&T System V) .. History (continued) .. The unix Operating System .. Multi-tasking, Time Sharing .. Multi-user .. Network Capabilities .. Portability .. Flexibility .. Software Available .. Virtual Memory .. Case Sensitivity .. unix Philosophy .. Exercises .. 132 File File and Directory Names .. Length .. Conventions .. Structure of Directories, Files .. Permissions/File Access Modes .. chmod: Change Mode (Permissions) .. Exercises .. 20iiiCONTENTS3 Tour of the File : Root .. : Commands .. : Devices .. : Management.

3 Home Directories .. : Libraries .. : Temporary Directories .. : Directories .. : Administration .. : System Mailboxes .. : Spooling Areas .. : Temporary Directory .. : Directories .. : Berkeley Binaries .. : Demonstration .. : Include Files .. : Local Programs .. : More Binaries .. : Shareable Directories .. 25/usr/share/lib/dict: Dictionary .. 25/usr/share/lib/Insight: Documentation .. 26/usr/share/doc: linux Documentation .. 26/usr/share/lib/spell: Speller .. 26/usr/share/lib/terminfo: Terminal Database .. 26/usr/share/manand/usr/share/catman: Manuals . : Temporary .. Exercises .. 274 Input/Output Redirection .. <: Input Redirection .. >,>>: Standard Output.

4 >,>&: Standard Diagnostic (Error) Output .. |: Pipes .. Pipes and Redirections .. : Background Processing .. (Wildcards) .. : Any Character(s) .. [,]: List of Characters .. ?: Any Single Character .. {,}: Alternatives (except Korn Shell) .. \: Escape .. Shell/Job Control .. : list background jobs .. : suspend a job .. : send a job in the backgroup .. : bring a job in the foreground .. : kill a job .. Sample session .. C Shell .. : Search Path .. Tenex Shell .. Bourne Shell .. PATH .. history .. alias .. Korn Shell .. : Search Path .. history .. Other Miscellaneous Commands .. Bash Shell .. : Search Path .. history.

5 Exercises .. 465 Basic File Permissions .. Passwords .. Root Password .. SSH .. TCP Wrappers .. Exercises .. 516 Commands A Command is a File .. Syntax .. Login Related Commands .. Logging On .. Changing Password .. Logging Out .. Help .. : Manual Pages .. Manuals on CDs .. File system Commands: Directories .. : Change Directory .. : Make Directory .. : Remove Directory .. : Print Working Directory .. : Copy .. : Move .. File system Commands: Files .. : Listing .. : Copy .. : Move .. : Link .. : Update .. : Remove .. : Concatenate .. : Browser .. : Header .. : Tail End .. : Word Count .. : Difference.

6 : Type of File .. Printer Commands (Berkeley;lpr/lprm) .. : Line Printer .. : Line Printer Queue, Statistics .. : Line Printer Remove .. Printer Commands (System V;lp/cancel) .. : Line Printer .. : Line Printer Queue, Statistics .. : Line Printer Remove .. Printer Commands ( linux ;kprinter) .. User Related Commands .. : Who is On .. am i,whoami: Who Am I .. Other Miscellaneous Commands .. : Display Date .. : Clear the Screen .. Exercises .. 767 ed Editor .. Accessinged.. Moving Within a File .. Finding a Pattern .. s Substitute .. c Change Line .. a Append Text .. i Input Text .. Current Line .. p Print Line(s) .. d Delete.

7 W Write .. q Quit .. vi Visual Editor Introduction .. Invokingvi.. ,commandandinputmodes .. vi visual Editor vi mode.. Moving the Cursor .. ^f Forward One Screen .. ^b Backwards One Screen .. G End of File .. x,d Delete Character .. dd Delete Line .. yy Copy Line in buffer .. p Put Buffer .. u Undo .. (dot) Repeat .. vi visual Editor command mode.. :q Quit .. :w Write .. :r Read .. :num Line Number .. /string/ Finding a Pattern .. n Next .. :set all.. vi visual Editor input mode.. i Insert Mode .. a Append to Character Mode .. A Append to Line Mode .. r Replace Character.

8 R Replace Characters .. cw Change Word .. Other Editors .. Emacs.. Exercises .. 908 Electronic Mail at NRC .. Internetnode: Machine Naming Convention .. Mail Forwarders .. Mail Folders .. Signature Files .. Mail Aliases .. : Multi-purpose Internet Mail Extensions .. : Forwarding Mail .. : I m away from my desk .. Securely Accessing POP/IMAP Mailboxes .. SSH tunneling of email from unix to unix .. SSH tunneling of email from a Windows application toUNIX .. : bring remote mail to local system .. 101 Manualfetchmail.. 103 Automated/daemonfetchmailmode .. The Berkely (BSD) Mail Interface .. Sending Mail .. 104~rfilename: Read Filename .. 105~v: Invoking the Visual Editor.

9 Reading Mail .. 106n: Next .. 106p: Print .. 106num: Print messagenum.. 107s: Save .. 107 Sending a file to a printer .. 107h: Header .. 107d: Delete .. 107r: Reply .. 107s: Forward .. 108~m: Incorporating current message .. 108q: Quit .. Configuring Mail Behaviour .. Mail Folders .. 109 Creating a Folder .. 109 Reading from a Folder .. , a special folder .. Mail Aliases .. : Multi-purpose Internet Mail Extensions .. : ELectronic Mail .. Sending Mail .. 110 Standalone Mode .. 110 Within the Interface .. 112 Batch Mode .. Reading Mail .. 112n: Next .. 114s: Save .. 114p: Printing to a printer .. 114d: Delete current message .. 114viiiCONTENTSr: Reply to sender .. 114f: Forward .. 115q: Quit.

10 Configuring Mail Behaviour .. Mail Folders .. 118 Creating a Folder .. 118 Reading from a Folder .. 118 Changing Folders .. Mail Aliases .. : Multi-purpose Internet Mail Extensions .. 122 MIME andelm: receiving messages.. 122 MIME andelm: sending messages.. The Pine mail interface .. Sending Mail .. 123 Standalone Mode .. 123 Within the Interface .. 126 Batch Mode .. Reading Mail .. 126n: Next .. 128s: Save .. 128p: Printing to a printer .. 128d: Delete current message .. 128r: Reply to sender .. 128f: Forward .. 129q: Quit .. Configuring Mail Behaviour .. Mail Folders .. 131 Creating a Folder .. 131 Reading from a Folder .. 131 Changing Folders .. Mail Aliases .. : Multi-purpose Internet Mail Extensions.