Re: TWO_TASK env var

In article <4o2m19$rip$1_at_mhadg.production.compuserve.com> Larry <104105.3062_at_CompuServe.COM> writes:
>We just migrated to an HP/UX 9000, had to invoke an environmental
>variable called TWO_TASK so that sql*net would be properly used
>by a C program that calls sql*plus. Without this env var the
>process hangs in sqlplus and does not accomplish anything. With
>it properly invoked our background process successfully enters
>and exits sqlplus.

Take this with a grain of salt, since I am working from memory, but this is what I think TWO_TASK is really all about.

Oracle came from the VMS environment, where you can have separate code and data space (actually, P1 and P0) in your program. When it moved over to the other environments which didn't have this explicit separation (this was before version 7), programs could be linked so that every tool would be linked into the oracle executable. The two_task came about when it became possible to have a separate process running oracle, and a separate process running the tool, communicating by a program like sqlnet. This allows the tools and the oracle executable to be linked separately, so you don't have to relink oracle every time you change your c program.

Things are even more confusing, since there is an ambiguity between whether an instance is two task (as defined by the TWO_TASK in the init.ora) and whether the tools have been linked two task. The more recent Oracle's have renamed some of this stuff.

Check your installation guide for linkage instructions for sqlplus. See if your Pro*C manuals say anything about linking, too.

> I would love some info about this env var. We have HP/UX10,
>Oracle7.1.6, SQL*NET2.0. Any knowledge about why a c program
>calling sqlplus would hang without this variable being set? This
>var is mentioned in the installation guide from Oracle, but the
>manual does not explain the use or the need for this variable.
>

It hangs because it needs to be told to communicate by sqlnet, as opposed to something within its process space.

Hope this makes it clearer rather than muddier.

jg

>As always, thanks for time and consideration. Larry

-- 
Joel Garry               joelga_at_rossinc.com               Compuserve 70661,1534
These are my opinions, not necessarily those of Ross Systems, Inc.   <> <>
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