I think it is local to Kirk.
CDSECT or EDCDSECT is part of the C/C++ compiler package. Search for it in
the User's or Programming Guide -- I forget which. Works decently although
less than perfectly wonderfully.
- Good for MVS data areas because while the result may not be pretty, it is
technically correct and so perfectly usable. You can tweak the results if
you wish.
- Not as good IMHO for your own records because the result may look like
junk and therefore be hard to understand. If you tweak it then if your
record changes you have to re-tweak it after re-running CDSECT.
It tends to do a funky job on redefinitions. Working untested from memory,
if you code
A DS C
B DS C
C DS C
ORG *-3
X DS C
Y DS C
Z DS C
Probably the most meaningful C equivalent would be something like
union {
struct { char a; char b; char b; };
struct { char x; char y; char z; }; };
that is, you probably think of it as two alternative 3-byte areas. But
CDSECT tends to do
union { char a; char x; };
union { char b; char y; };
union { char c; char z; };
that is, as three areas each of which has two alternative names.
Charles
-----Original Message-----
From: IBM Mainframe Discussion List [mailto:IBM-MAIN@LISTSERV.UA.EDU] On
Behalf Of Barkow, Eileen
Sent: Friday, February 9, 2018 12:52 PM
To: IBM-MAIN@LISTSERV.UA.EDU
Subject: Re: Silly C problem adding hex 6C-psa.h - edcdsect
I do not see edcdsect.rexx anywhere. I do not think that we have rexx
installed on Unix.
-----Original Message-----
From: IBM Mainframe Discussion List [mailto:IBM-MAIN@LISTSERV.UA.EDU] On
Behalf Of Seymour J Metz
Sent: Friday, February 09, 2018 3:26 PM
To: IBM-MAIN@LISTSERV.UA.EDU
Subject: Re: Silly C problem adding hex 6C-psa.h - edcdsect
First, he didn't provide the script, only illustrated its use. Second CLIST
and REXX are two very different languages.
Kirk was showing the OMVS commands to use edcdsect.rexx.
--
Shmuel (Seymour J.) Metz
http://mason.gmu.edu/~smetz3
________________________________________
From: IBM Mainframe Discussion List <IBM-MAIN@listserv.ua.edu> on behalf of
Barkow, Eileen <ebar...@doitt.nyc.gov>
Sent: Friday, February 9, 2018 8:40 AM
To: IBM-MAIN@listserv.ua.edu
Subject: Re: Silly C problem adding hex 6C-psa.h - edcdsect
How do you run this script?
I tried it under UNIX and MVS as a rexx clist and get all kinds of errors.
$ ccsect
psa.h:: ccsect 1: FSUM7351 not found
edcdsect.rexx: ccsect 4: FSUM7351 not found $
-----Original Message-----
From: IBM Mainframe Discussion List [mailto:IBM-MAIN@LISTSERV.UA.EDU] On
Behalf Of Kirk Wolf
Sent: Friday, February 09, 2018 7:58 AM
To: IBM-MAIN@LISTSERV.UA.EDU
Subject: Re: Silly C problem adding hex 6C
It is better IMO to use EDCDSECT and create C header files for the system
DSECTS (PSA, ASCB, ASXB, etc), then you don't have to hard code offsets into
your code.
We have a little rexx shell script that we have been using for a dozen years
that invokes the assembler + EDCDSECT. It is simple to add recipes to your
Makefile for whatever system headers you want.
For example:
psa.h:
echo " IHAPSA " > asm_temp.s
echo " END" >> asm_temp.s
edcdsect.rexx asm_temp.s > psa.h
Then you can do:
#include "psa.h"
struct psa* pPSA = (struct psa*)0;
struct ascb* pASCB = (struct ascb*)pPSA->psaaold; ...
EDCDSECT is not perfect, but it generally works pretty well.
Kirk Wolf
Dovetailed Technologies
http://secure-web.cisco.com/12TWE8dXdbRVXzcJYbEA-byAvN6cSXeP1rhfnhh7Pa0wEeRF
7mWSLoZ6goOOhN-t5hX_thEGjwBDQ5gSI8NqWhi6LjidYzSAXzKkKFzZw3nd2Y0Js2LoiFS29Ylj
bOBrGQX0f5bWALkUNdJIOmT6GJgUYeSW61vUrayUrir72UXGxNNWqdq9kYlKXrQjKMr_yqb8lasC
wZfSutQl221odQZH4QvP-FhM4k39wet0AE_TrUe5bv9Px9RQd2eHVSYBdtn0PQ17RvquapDqCGAn
vV2mr66eC9N9mIBW2tOH7-hg7A6bAgssqsCVXtCObu9iRexaPkE_5NNvnjIuly_-Go7oOwjv6eUz
9PN0PhYlIzIHKBfXfeEOACeMlYo6mW72dXK972uIiNQmgc9gGw3YjN9KTaRfxUdIMuDiFPkRvblp
Zt-NOXRidkWltUZ8BPzHr/http%3A%2F%2Fdovetail.com%0D%0A%0D%0AOn%20Fri%2C%20Feb
%209%2C%202018%20at%206%3A02%20AM%2C%20Bernd%20Oppolzer%20%3Cbernd.oppolzer%
40t-online.de>
wrote:
> More simple ... the pointers don't need to be int pointers; char
> pointers are just as good:
>
>
> #include <stdlib.h>
> #include <stdio.h>
> #include <string.h>
> #include <errno.h>
>
> int main (int argc, char **argv)
>
> {
> char *PSA;
> char *ASCB;
> char *ASXB;
> char *ASXBP;
> char *JNPI;
> char jobname[9];
>
> PSA = (char *) 0x224; /* address of PSAAOLD */
> ASCB = (char *) (*PSA);
> printf ("ASCB = %p\n", ASCB);
> ASXB = ASCB + 0x6c;
> printf ("ASXB = %p\n", ASXB);
> ASXBP = (char *) (*ASXB);
> printf ("ASXBP = %p\n", ASXBP);
> JNPI = ASXBP + 0xC0;
> printf ("JNPI = %p\n", JNPI);
> memcpy (jobname, JNPI, 8);
> jobname [8] = 0x00;
> printf ("jobname = %s\n", jobname); }
>
>
>
> Am 09.02.2018 um 12:57 schrieb Bernd Oppolzer:
>
>> This is a slightly modified version of jn2.c:
>>
>> #include <stdlib.h>
>> #include <stdio.h>
>> #include <string.h>
>> #include <errno.h>
>>
>> int main (int argc, char **argv)
>>
>> {
>> int *PSA;
>> int *ASCB;
>> int *ASXB;
>> int *ASXBP;
>> int *JNPI;
>> char jobname[9];
>>
>> PSA = (int *) 0x224; /* address of PSAAOLD */
>> ASCB = (int *) *PSA;
>> printf ("ASCB = %p\n", ASCB);
>> ASXB = (int *) ((char *) ASCB + 0x6c);
>> printf ("ASXB = %p\n", ASXB);
>> ASXBP = (int *) *ASXB;
>> printf ("ASXBP = %p\n", ASXBP);
>> JNPI = (int *) ((char *) ASXBP + 0xC0);
>> printf ("JNPI = %p\n", JNPI);
>> memcpy (jobname, JNPI, 8);
>> jobname [8] = 0x00;
>> printf ("jobname = %s\n", jobname);
>> }
>>
>> a) pure ANSI C
>>
>> b) some intermediate steps and variables removed
>>
>> c) there is a subtle error in the original version:
>> the terminating hex zero in jobname is missing. I added it.
>>
>> Caution: untested ...
>>
>> Kind regards
>>
>> Bernd
>>
>>
>>
>> Am 09.02.2018 um 12:41 schrieb Bernd Oppolzer:
>>
>>> .. in fact, the original source contains some parts,
>>> which are not ANSI C, for example cout (which is C++)
>>> and iostream.h (which is also part of the C++ library).
>>>
>>> Because I don't like C++ ... and the program claims to be
>>> a C program, I would (as a QA person) force the coder to
>>> eliminate these parts of the code.
>>>
>>> Kind regards
>>>
>>> Bernd
>>>
>>>
>>> Am 09.02.2018 um 12:32 schrieb Bernd Oppolzer:
>>>
>>>> Am 09.02.2018 um 07:45 schrieb Elardus Engelbrecht:
>>>>
>>>>> Bernd Oppolzer wrote:
>>>>>
>>>>> To be more pedantic, use additional parantheses:
>>>>>> ASXB = (int *) (((char *) ASCB) + 0x6c);
>>>>>>
>>>>> I C ( "I see" ;-D )
>>>>>
>>>>> Seriously, I find this whole thread very interesting.
>>>>>
>>>>> Just a question please and please excuse my ignorance.
>>>>>
>>>>> Are these discussions about C or C++?
>>>>>
>>>>> Because:
>>>>>
>>>>> OP said 'crawl my way around C/C++'
>>>>> Shmuel and Paul are talking about C and Charles talked about C++ (for
>>>>> his 2 templates)
>>>>>
>>>>> Feel free to teach me so I can C...
>>>>>
>>>>> TIA!
>>>>>
>>>>> Groete / Greetings
>>>>> Elardus Engelbrecht
>>>>>
>>>>>
>>>>>
>>>> I went back to the original post which started the thread;
>>>> the OP said "C / C++", but posted a C program (called jn2.c),
>>>> so I guess, the discussion should in fact be about C.
>>>>
>>>> a) It's all pure C syntax
>>>> b) with C++, the filetype would have been "cpp"
>>>>
>>>> HTH, kind regards
>>>>
>>>> Bernd
>>>>
>>>> ----------------------------------------------------------------------
>>>> For IBM-MAIN subscribe / signoff / archive access instructions,
>>>> send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
>>>>
>>>>
>>>
>> ----------------------------------------------------------------------
>> For IBM-MAIN subscribe / signoff / archive access instructions,
>> send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
>>
>>
> ----------------------------------------------------------------------
> For IBM-MAIN subscribe / signoff / archive access instructions,
> send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
>
----------------------------------------------------------------------
For IBM-MAIN subscribe / signoff / archive access instructions,
send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
________________________________
This e-mail, including any attachments, may be confidential, privileged or
otherwise legally protected. It is intended only for the addressee. If you
received this e-mail in error or from someone who was not authorized to send
it to you, do not disseminate, copy or otherwise use this e-mail or its
attachments. Please notify the sender immediately by reply e-mail and delete
the e-mail from your system.
----------------------------------------------------------------------
For IBM-MAIN subscribe / signoff / archive access instructions,
send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
----------------------------------------------------------------------
For IBM-MAIN subscribe / signoff / archive access instructions,
send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
----------------------------------------------------------------------
For IBM-MAIN subscribe / signoff / archive access instructions,
send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
----------------------------------------------------------------------
For IBM-MAIN subscribe / signoff / archive access instructions,
send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
