| SAS Companion for UNIX Environments |
UNIX is a multitasking system, so
you can run multiple processes
at the same time. For example, you can have one process running in the foreground
and three in the background. A foreground process
executes
while you wait for the prompt; that is, you cannot execute additional commands
while the current command is being executed. After you enter a command, the
shell starts a process to execute the command. After the system executes the
command, the shell displays the prompt and you can enter additional commands.
A background process
executes independently of the shell.
After you enter a command, the shell starts a process to execute the command
and then issues the system prompt. You can enter other commands or start other
background tasks without waiting for your initial command to execute. You
can run the SAS System in the foreground or in the background.
Note:
Both the C shell and the Korn shell include commands
that allow you to move jobs among three possible states: running in the foreground,
running in the background, and suspended. ![[cautend]](../common/images/cautend.gif)
You can run SAS in the SAS windowing environment, in interactive line
mode, or in batch mode.
-
Windowing environment
-
You interact with SAS through windows using your keyboard,
mouse, pull-down menus, pop-up menus, and icons. The windowing environment
includes, but is not limited to, the Explorer, Program Editor, Output, Log,
and Results windows. Explorer is a windowing environment for managing basic
SAS software tasks such as viewing and managing data sets, libraries and members,
applications, and output. The SAS Explorer is a central access point from
which you can
The
Program Editor, Log, and Output windows enable you to edit
and execute SAS programs and display output.
If you want to use the windowing environment, you can start your SAS
session as a foreground process or as a background process (by adding an ampersand
(&) to your SAS command line).
-
Interactive line mode
-
You enter SAS statements line
by line in response to prompts issued by the SAS System. SAS reads the source
statements from the terminal as you enter them. DATA and PROC steps execute
when
To use interactive line mode, you must run SAS in the
foreground.
-
Batch mode
-
To run SAS in
batch mode, you specify your SAS application name
in the SAS command. You can run batch mode in the foreground, in the background
by specifying an ampersand at the end of the SAS command, or submit your application
to the batch queue by using the
batch,
at,
nohup,
or
cron UNIX commands. If you start your
application with one of these UNIX commands, then you log off of your system
and your application will complete execution. If your application contains
statements that start an interactive procedure such as FSEDIT, then you need
to run your batch application in the foreground.
Ask your
system manager which interface or mode of operation
is the default at your site.
Copyright © 1999 by SAS Institute Inc., Cary, NC, USA. All rights reserved.
