Read and write NFS-files 
Author Message
 Read and write NFS-files


We use IBM-APL2/6000 on a RS6k-370 with AIX 3.2.5 and today we got once more an
old problem.
When we want to handle a large (greater 8 MB, width > 2000 character) sequential
file, which resides on a, from a VAX, NFS-mounted filesystem we will get a lot
of failures:

1. we can read the file contents, but we cannot write to this file

2. we cannot read the file contents and get undocumented returncodes (78)

For the work with files we use the with APL2/6000 distributed library
[ )LIB 1 FILE ].

To avoid this situation we did the following - we transferrred the file
via ftp to our local JFS-filesystem and the handling of the file is no longer a problem. But we prefer to use the NFS-solution because the VAX use a RAID-system and we only a mirroring of our harddisk for data backup and on the other hand
we are limited with the size of our harddisk, because we have a lot of sensible and large files.

Any ideas?

Thanks in advance


Gerald Kroboth, Ing.

Abt. OMZ                          phone:   +43 1 277 22-3791  
Scheydgasse 41                    fax:     +43 1 277 22-187  
A-1211  Wien

Tue, 21 Jul 1998 03:00:00 GMT  
 Read and write NFS-files
Our auxiliary processors do not contain code to handle NFS files
in any special way.  We issue standard file calls to the operating
system, and if the files are NFS, it handles them as it will.
We try to map return codes we expect from the operating system
to ap return codes (negative numbers) but we haven't anticipated
them all.  Any positive return codes you are getting are from
the C system file errno.h.  The function CHECK_ERROR in
public workspace 2 AIX can be used to get the error name from
errno.h.  These names are sometimes enough to get a better
idea of what is wrong.   However, from past experience with other
customers who had problems with NFS files, the problems were
NFS-related, not reliably reproducble, and would tend to vanish
when the system was re-booted or the NFS server was re-started.

If you want some additional help please write to our help

as much detail as possible about which return codes you got
from which ap commands.   We should also discuss what level
of APL2/6000 you are running.  We have added more extensive
error mapping in the service.

Nancy Wheeler
APL Products and Services, IBM

Fri, 24 Jul 1998 03:00:00 GMT  
 [ 2 post ] 

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