RE: Service Program Signatures and Change Management

David;

Service programs are bound at program creation, not at run time. When a
service program object is deleted (through a recompile/updsrvpgm...) and a
program/service program that uses it is run the "links" are broken. At that
point a dynamic bind occurs and the program and new service program are
rebound. If for whatever reason the signatures do not match the bind fails,
otherwise the new service program is now bound "permanently" to the caller.
This is how you get the performance benefits of static binding and yet don't
have to recompile the world when a service program changes.

Duane Christen
 

-----Original Message-----
From: midrange-l-bounces@xxxxxxxxxxxx
[mailto:midrange-l-bounces@xxxxxxxxxxxx]On Behalf Of David Gibbs
Sent: Thursday, February 16, 2006 1:17 PM
To: Midrange Systems Technical Discussion
Subject: Re: Service Program Signatures and Change Management


Fleming, Greg (ED) wrote:
> I thought service programs were bound to the calling programs at
> run-time.  

They are, but at compile time a signature (similar to a file format
level identifier) is pulled in from the service program and embedded in
the program ... if the program tries to bind to the service program at
runtime and the signature doesn't match, you get an error.

Binder source can be used to control the signatures.

david