Re: How to call a RPG program from a RPG program?

Hi, Birgitta:

This might have been done to ensure that a "full dynamic call" was used ...

RPG/400 and ILE RPG IV compilers generate code that resolves a pointer to a *PGM just once, and then re-uses that pointer for all subsequent CALLs. This can cause problems if you recompile the *PGM and do not use REPLACE(*YES), thus deleting the old *PGM object. Any programs that have resolved to that *PGM will "blow up" on subsequent calls, with something like:

MCH3402 40 Tried to refer to all or part of an object that no longer exists

There are ways to avoid this, but many RPG programmers are not aware of those techniques. So, they may have come up with this method.

(Of course, we cannot know for certain, unless you can hunt down and ask the original author.)

Hope that helps,

Mark S. Waterbury

> On 6/20/2012 1:20 AM, Birgitta Hauser wrote:

A new way to call a RPG program from a different RPG program!
I found the following code snippet this morning in a program written in
April 2012!!!
Both programs are written in RPGIV!!!
Aaaaaaaaaarrrrrrgh!

D DW_System PR 10i 0
d cmd 2048 varying value

D dsallpf ds qualified
D fil 10A
D lib 10A
...
/Free
dw_system('CALL PGM(DSYUNIQUE) PARM('''+
dsallpf.fil+''' '''+
dsallpf.lib+''' ''0'')');
...
/End-Free
P DW_System B
D DW_System PI 10i 0
D cmd 2048 varying value

d cmdval s 2046 based(cmdval_p)
c eval cmdval_p=%addr(cmd)+2
c eval cmdlen=%len(cmd)
c call 'QCMDEXC' 50
c parm cmdval
c parm cmdlen 15 5
c 50 return -1
c return 0
P DW_System e


Mit freundlichen Grüßen / Best regards


Birgitta Hauser


"Shoot for the moon, even if you miss, you'll land among the stars." (Les
Brown)

"If you think education is expensive, try ignorance." (Derek Bok)

"What is worse than training your staff and losing them? Not training them
and keeping them!"


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