fwrite() under Ultrix 4.0 on DECStation 5000..

[Valerie Caro]

I have written a program that converts a data file in one format to another 
format.  The source file is a KBVISION Tokenset file and the output format is an 
ISR2 frame file.  (If these terms don't mean anything, that is ok - they are two 
different, but conceptual simular DB files used in computer vision research.)  
My program uses a supplied library to read in the KBVISION file and uses 
fwrite() to write out the output file.

The program works fine on a Sun4 runninf SunOS 4.1.

The problem is on the DECStation.  We have three DECStation 5000/200s running 
Ultrix 4.0.  Each machine has a local disk and the disks are cross mounted with 
NFS.  We also have a 12 member VAXCluster (mostly VAXStation 2000s, with 2 MVIIs 
and a VAXStation 3100).  Some of the VAXes run UCX and all of the VMS user disks 
are NFS exported and mounted on the DECStations.  When I run the program on one 
of the DECStations with the output file on a NFS mounted VMS disk, the program 
works correctly and produces a corectly sized output file, which can be 
successfully read in by the ISR2 system.  When I set the output to a local disk, 
I get a file that is slightly shorter and at least the beginning of the file is 
crupted.  When I set the output to a NFS mounted disk on one of the other 
DECStations, the file is even shorter and is also crupted.   I am pretty sure it 
is not my program, since it works perfectly on the Sun4 and on the DECStation 
when the output file is in a NFS mounted VMS file system.  I am not much of a 
UNIX user (been using VMS for some time now and only started using UNIX 
recently) and don't have the slightest idea where to look.

		Robert Heller
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