PROBLEM:

I am running out of space and want to compress my raw data files.  
Can I access the data without uncompressing it. (Yes.) How?
The compressed data are stored on:
     1. UniTree
     2. UNIX disk

*********************************

SOLUTION:

SAS can access compressed raw data files using the PIPE feature of the 
FILENAME statement.  Basically you will issue the UNIX uncompress 
command and have the uncompressed data feed into the SAS program.
Here are some examples:

1. Accessing compressed files on UniTree.  

Compressed raw data files do not have to be moved to UNIX disk to be used 
by SAS.  The following code obtains raw data directly from a compressed 
file called 'full.housing.Z' stored on UniTree.

     filename raw pipe 'unitree get full.housing.Z  -  | uncompress ';
     data one;
     infile raw;
     input 

NOTE: The dash (-) in the FILENAME statement is not an error; it must
appear, with a space before and after it, just as shown above.

The file 'full.housing.Z' never ends up on disk, so it will save a
lot of time and space.


2. Accessing compressed local files.

Local files can be accessed in the same manner as UniTree files with
a slightly different filename statement.  In this example we
are trying to read the data in a file called 'crush.house1.Z' that is
located in my directory called 'housing'.

     filename here pipe 'uncompress -c ~/housing/crush.house1.Z';
     data two;
     infile here;
     input 

The file 'crush.house1.Z' remains in compressed form in the 'housing'
directory, saving time and space.



Further Documentation: help unitree, help sas, man uncompress,  
SAS Companion for UNIX.