SAS Companion for the Microsoft Windows Environment |
A pipe is a channel of communication between two processes. A process with
a handle to one end can communicate with another process that has a handle
to the other end. With the SAS System and Windows NT, this means that you
can use a specialized Windows application to provide information to your SAS
session or vice versa.
Note: Pipes and named pipes are supported in SAS only
under Windows NT. Windows 98 and Windows 95 can support named pipes, but
only as a client.
Pipes can be one-way or two-way. With a one-way pipe,
one application can only write data to the pipe while the other application
reads from it. With a two-way pipe, both applications can read and write data.
There are two types of pipes:
- unnamed pipe
- handles one way communication. Also called
an anonymous pipe (or simply pipe), it is typically used to communicate between
a parent process and a child process. Within SAS, the SAS System is the parent
process that invokes (and reads data from) a child process.
- named pipe
- handles one-way or two-way communication
between two unrelated processes. That is, one process is not started by the
other. In fact, it is possible to have two applications communicating over
a pipe on a network. You can use named pipes within SAS to communicate with
other applications or even with another SAS session.
Copyright 1999 by SAS Institute Inc., Cary, NC, USA. All rights reserved.