Subject: Fortran 90 Shareware Product announcement
Date: May 16, 1995

Programmers doing database work, or programmers that need a key-based 
access method to manipulate dataset will be interested in the two new 
Fortran 90 modules just made available Garnatz and Grovender, Inc. 

The "ISF" and "PKF" modules implement a ISAM/VSAM/btree file structure, and
a Positional Key file structure.  These modules are available for
testing via anonymous ftp.  If you use them, or incorporate them
into a program, you are requested to register and pay a license fee.

1) The "ISF" file structure is an "Indexed Sequential" structure.  A totally 
absent file type in standard Fortran. This structure is very useful because
it enables one to access data by a key, and then read sequentially forward 
or backward.  One can also delete a record by key, and skip to the 
beginning or end of a file.

2) The "PKF" module is an useful as a building block for other kinds
of access, such as binary trees or linked lists.  This module is a 
"Positional Key" file organization that is different than standard 
Fortran ACCESS='DIRECT' in that when a record is written, the write 
routine returns a key.  This key is needed as an argument to retrieve 
the record later by the read routine.  "PKF" used twice in the "ISF" 
module, once for the data and once for the keys.

Applications:
1) Programmers porting code from CDC Cyber 170/180 mainframes will recognize the
   similar functionality to Cyber Record Manager FO=IS and FO=DA.
2) Programmers porting codes from DEC Fortran that have used the 
   non-standard ACCESS='KEYED' file type.

Garnatz and Grovender, Inc.
email: gginc@winternet.com
URL:   http://www.winternet.com/~gginc
ftp:   ftp.winternet.com/users/gginc

DEC is registered trademarks of Digital Equipment Corporation
CDC and Cyber are registered trademarks of Control Data Corporation 
