Re: Persistence

["Larry Ducie" <larry_ducie@xxxxxxxxxxx>]

Hi Tony,

<snip>
As far as I know, each time a subprocedure is called, it's variables
are all initialized, so this means that, for each subprocedure, I need
a global set of variables in the main procedure that it can store
stuff in.  This just doesn't seem to go with what I believe
subprocedures were designed for.  If I want to use one of these
subprocedure in another program, I have to duplicate the global
variables from the main program.
</snip>

You can prevent your local variables from being re-initialised every time a 
subproc is called by using the STATIC keyword on your local variables - the 
variables are still local to your subprocedure, it's just that the compiler 
allocates STATIC storage to hold them - they're no longer treated as 
automatic variables.

Have a look at the thread entitled "Static procedure variables - how to 
re-initialise?" that has run over the last few days for more information 
about their use.

The biggest consideration is the fact that setting on *INLR in the program 
does not clear them down, so subsequent calls to the program will have 
initialised global variables, but un-initialised STATIC local variables.

It would appear that the two contending approaches to re-initialise these 
fields are to:
1) Put your subprocs into a module and create a *SRVPGM in a named 
activation group. Reclaim the activation group to reclaim all static 
storage, and thus clearing static local variables.
2) Include an optional (*nopass or *omit - your preference) parameter to the 
subprocedures and use it as a "mode" flag to initialise the variables.

HTH

Cheers

Larry Ducie