- During the l960s, General Electric, MIT, and Bell Labs worked on a
time-sharing operating system (MULTICS).
- Ken Thompson (Bell Labs), who worked on the MULTICS project, wanted
to retain Space Wars for his use; during the early 1970s, he
created an operating system to run on a PDP7 (UNICS --| UNIX).
- Because AT&T was a monopoly at that time, they could not sell the
operating system, they made it available to universities:
Carnegie Mellon and UC Berkeley.
- During the 1980s, the end of the AT&T monopoly and the need for an
operating system for 16-bit microcomputers created a market
for UNIX.
- Current Versions:
System V (Bell labs), AIX (IBM), UC Berkeley
- UNIX Reference Books:
any UNIX book is good -- System V is slightly more preferable.
Accessing UNIX:
Turn on the power for the terminal -- you must wait a few moments until the RISC System/6000 prompt is displayed. Note: UNIX is case-sensitive! Be sure the CAPS-LOCK key is OFF.
| login: [user id] | six letters (last) + 2 letters (first) |
| password: [ password] | social security number (no hyphens) |
The dollar sign ($) prompt indicates that you have successfully accessed the UNIX operating system.
| $ pwd | shows where you are on the system (current directory) |
| $ ls -FCA | shows what files and directories exist in current directory |
| $ who | shows the users currently on the system |
| $ passwd | allows the user to change his/her password |
Special Characters:
Directory Tree Structure:
Files are maintained in UNIX using a tree structure. There is a single root directory (/) which may be further divided into subdirectories; each subdirectory may in turn be further divided into subdirectories. Any of these areas are capable of storing files.
Three directories have special significance:
| root directory | the top-level directory from which all others descend |
| home directory | the directory to which you are assigned when you log in " /www.d/wwwserver/yourusername " |
| current directory | the directory to which you are currently assigned |
The following UNIX commands are appropriate to navigating the tree structure organization:
| $ cd | change to home directory |
| $ cd / | change to root directory |
| $ cd [ path ] | change to directory specified by (path) |
| $ cd .. | change to directory one level up (parent directory) |
| $ mkdir [direct_name] | to "make" a new directory |
| $ rmdir [direct_name] | to "remove" an obsolete directory |
Objects (i.e., files and subdirectories) which are "underneath" the current directory in the tree structure may be referenced by a partially-qualified name; otherwise, they must be referenced by a fully-qualified name.
| /www.d/wwwserver/scrocco/public_html/img/my.gif | fully-qualified name |
| public_html/img/my.gif | partially-qualified name (from directory /www.d/wwwserver/scrocco) |
File Maintenance:
| $ cat [filename] | display contents of [filename], without pause |
| $ pg [filename] | display contents of [filename], with pause - use |
| $ cp [from] [to] | "copy" file [from] to new file [to] |
| $ mv [from] [to] | "move" file [from] to new file [to] |
| $ rm [old] | "moves" file [old] |
Mail Utility:
| $ mail [user id] | to send mail to another user |
| to retrieve your own mail |
Help Utilities:
| $ man [command] | to obtain help concerning [command] |
| use [SpaceBar] to advance screens |
Miscellaneous Commands:
| $ env | display UNIX environment |
| $ stty | display terminal settings |
| $ set | display other settings |