topic Re: not having luck with set process/dump in Operating System - OpenVMS

not having luck with set process/dump

SAMI AHMAD — Sat, 28 Mar 2009 19:06:09 GMT

I am trying to create a dump file for a detached process that is crasing with
%SYSTEM-F-ACCVIO, access violation, reason mask=00, virtual address=0000000000000000, PC=0000000000037FDC, PS=0000001B

but it does not create a dump file
I have two questions:

1- is doing the SET PROCESS/DUMP enough before starting the detached process to capture the dump or I need to do more?

2- normally reason mask has values like 1 ,2 ,4 etc which means something but what reason mask of 00 means? in which situations can we get access violation with no reason mask?

thanks

Re: not having luck with set process/dump

SAMI AHMAD — Sat, 28 Mar 2009 19:14:33 GMT

also will I get a dump if I do the following since this is the way the application is started .

$set process/dump
$spawn/nowait/proc=TEST RUN/NODEBUG TEST.EXE

Re: not having luck with set process/dump

Steven Schweda — Sat, 28 Mar 2009 19:23:41 GMT

> [...] but what reason mask of 00 means?

It means that your big problem is "virtual
address=0000000000000000", often the result
of trying to use a NULL pointer in C.

Re: not having luck with set process/dump

SAMI AHMAD — Sat, 28 Mar 2009 19:26:23 GMT

sorry i didnt provide the complete picture, the application is spawning two types of prcess I detached and one not detached

1)$spawn/nowait run/nodebug test1.exe
this one i found out i can produce a dump by putting run/dump

2)$spawn/nowait test2
how do i produce a dump for this process?

Re: not having luck with set process/dump

Hoff — Sat, 28 Mar 2009 21:41:39 GMT

Here is how to use the OpenVMS Debugger with a detached process, as well as other debugging techniques:

http://64.223.189.234/node/803

Here is how to debug an access violation on OpenVMS:

http://64.223.189.234/node/800

And if you'd like to know what the meanings of the various bits within the reason (bit) mask mean when the individual bits are set or when they are clear, then take the time to read the available documentation:

$ help /message/facility=system accvio

Re: not having luck with set process/dump

Volker Halle — Wed, 01 Apr 2009 10:12:27 GMT

Sami,

a reason mask of 00 indicates a 'faulting data read', i.e. an invalid source address pointing to a non-accessible page.

SPAWN does not pass the image-dump flag to the spawned subprocess, so you need to issue the SET PROC/DUMP command in the context of the subprocess, before running the image.

Volker.