IBM Mainframe Forum

by **sensuixel** » Tue Jul 24, 2012 6:13 pm

Hello,

I'm trying to invoke DFSORT from Assembler.

So I read DFSORT Application Programming Guide (ice1ca50) and I wrote this code

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ASMSRCT2 CSECT
INITL 12,EQU=R BASE REG = 12, R15 = 15
OPEN_FIC EQU *
OPEN (SORTIN,(INPUT))
OPEN (SORTOUT,(OUTPUT))
LA R1,PARLST LOAD ADDR OF PARAM POINTER IN R1
LINK EP=SORT
ENDFIC CLOSE SORTIN
CLOSE SORTOUT
RCNTL RC=0
* WORKING STORAGE
* EXTENDED PARAMETR LIST
PARLST DC A(CTLST) ADDRESS OF CONTROL STATEMENTS
PL2 DC A(0) ADDRESS OF E15 ROUTINE
PL3 DC A(0) ADDRESS OF E35 ROUTINE
PL4 DS A USER EXIT ADDRESS CONSTANT
PL5 DC F'-1' INDICATE END OF LIST
CTLST DS 0H CONTROL STATEMENTS AREA
DC AL2(CTL2-CTL1) LENGTH OF CHARACTER STRING
CTL1 DC C' SORT FIELDS=(1,4,CH,A)'
CTL2 EQU *
* FILE DCB
SORTIN DCB DDNAME=SORTIN,DSORG=PS,MACRF=(GL) EODAD=ENDFIC
SORTOUT DCB DDNAME=SORTOUT,DSORG=PS,MACRF=(PM)
*
END ASMSRCT2

I get the following sysout

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ICE143I 0 BLOCKSET SORT TECHNIQUE SELECTED
ICE250I 0 VISIT http://www.ibm.com/storage/dfsort FOR DFSORT PAPERS, EXAMPLES A
ICE000I 0 - CONTROL STATEMENTS FOR 5694-A01, Z/OS DFSORT V1R10 - 14:17 ON TUE J
SORT FIELDS=(1,4,CH,A)
ICE201I G RECORD TYPE IS F - DATA STARTS IN POSITION 1
ICE751I 0 C5-K51707 C6-K51707 C7-K54603 C8-K51707 E4-K51707 C9-BASE E5-K55337
ICE193I 0 ICEAM2 INVOCATION ENVIRONMENT IN EFFECT - ICEAM2 ENVIRONMENT SELECTED
ICE252I 1 PARMLIB OPTIONS WERE MERGED WITH INSTALLATION MODULE DEFAULTS
ICE088I 1 APIASMT2.APIASMT2. , INPUT LRECL = 300, BLKSIZE = 27900, TYPE
ICE093I 0 MAIN STORAGE = (MAX,4194304,4194304)
ICE156I 0 MAIN STORAGE ABOVE 16MB = (4136944,4136944)
ICE127I 0 OPTIONS: OVFLO=RC0 ,PAD=RC0 ,TRUNC=RC0 ,SPANINC=RC16,VLSCMP=N,SZERO=Y
ICE128I 0 OPTIONS: SIZE=4194304,MAXLIM=1048576,MINLIM=450560,EQUALS=N,LIST=Y,ER
ICE129I 0 OPTIONS: VIO=N,RESDNT=ALL ,SMF=NO ,WRKSEC=Y,OUTSEC=Y,VERIFY=N,CHALT
ICE130I 0 OPTIONS: RESALL=4096,RESINV=0,SVC=109 ,CHECK=Y,WRKREL=Y,OUTREL=Y,CKPT
ICE131I 0 OPTIONS: TMAXLIM=4194304,ARESALL=0,ARESINV=0,OVERRGN=16384,CINV=Y,CFW
ICE132I 0 OPTIONS: VLSHRT=N,ZDPRINT=Y,IEXIT=N,TEXIT=N,LISTX=N,EFS=NONE ,EXIT
ICE133I 0 OPTIONS: HIPRMAX=OPTIMAL,DSPSIZE=MAX ,ODMAXBF=0,SOLRF=Y,VLLONG=N,VSAM
ICE235I 0 OPTIONS: NULLOUT=RC0
ICE084I 0 EXCP ACCESS METHOD USED FOR SORTOUT
ICE084I 0 EXCP ACCESS METHOD USED FOR SORTIN
ICE750I 0 DC 27900 TC 0 CS DSVVV KSZ 4 VSZ 4
ICE752I 0 FSZ=93 RC IGN=0 E AVG=300 0 WSP=37 C DYN=0 0
ICE751I 1 DE-K50430 D5-BASE D9-BASE E8-K51707
ICE090I 0 OUTPUT LRECL = 300, BLKSIZE = 27900, TYPE = FB
ICE080I 0 IN MAIN STORAGE SORT
ICE055I 0 INSERT 0, DELETE 0
ICE054I 0 RECORDS - IN: 17, OUT: 17
ICE134I 0 NUMBER OF BYTES SORTED: 5100
ICE253I 0 RECORDS SORTED - PROCESSED: 17, EXPECTED: 93
ICE199I 0 MEMORY OBJECT STORAGE USED = 0M BYTES
ICE180I 0 HIPERSPACE STORAGE USED = 0K BYTES
ICE188I 0 DATA SPACE STORAGE USED = 0K BYTES
ICE052I 0 END OF DFSORT

According to this SYSOUT, the SORTIN file seems to be read normally but i end up with an empty SORTOUT file
after having run this JCL

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//APIASMT2 EXEC PGM=APIASMT2
//STEPLIB DD DISP=SHR,DSN=EAPICH.AGRR.LOAD
//SORTIN DD DISP=SHR,DSN=EAPICH.TD.FB300
//SORTOUT DD DISP=(,CATLG),DSN=EAPICH.TD.OUT,
// RECFM=FB,LRECL=300,AVGREC=M,SPACE=(1,(1,1),RLSE)
//SYSOUT DD SYSOUT=*

I'm actually reading MVS Programming : Assembler Services Reference , volume 2 (IAR - XCT) ( iea2a9a0) to look further
on the Link macro, I may be missing something here but If anyone has an idea ...

by **dick scherrer** » Tue Jul 24, 2012 9:17 pm

Hello,

I've not invoked sort this way, but in other languages, SORT controls the SORTIN and SORTOUT datasets. They should not be opened by the code invoking the sort.

Was the output dataset successfully created or did the catalog fail as it already existed?
Subsequent info says that being already cataloged was NOT an issue. d

Hopefully, this is just an experiment as invoking the sort to do nothing but sort the input and create the output wastes system resources.

To do something like i believe you want, the sort is typically invoked and then user "exit"s are used to control pre- and post-sort processing.

If there continues to be a problem, let us know and your topic can be relocated to the DFSORT part of the forum.

by **steve-myers** » Tue Jul 24, 2012 10:18 pm

Read Mr. Scherrer's comments carefully. As Mr. Scherrer says, you do not open the SORTOUT dataset until the sort has completed, and then, presumably, you open it for input so you can read the sorted dataset. Your way, you effectively lost the sort generated SORTOUT output.

Though the sort documentation is unclear about this, a program can dynamically call sort in three ways.

Simulating JCL. Your JCL must specify a message dataset, a SYSIN dataset, and the SORTIN and SORTOUT datasets.
Using an AMODE 24/RMODE 24 compliant parameter list. The sort DD statements depend on the contents of the parameter list.
Using an AMODE ANY / RMODE ANY compliant parameter list. DFSORT calls this an "extended parameter list." The sort DD statements depend on the contents of the parameter list.

All the sort products use the same parameter list for a "basic" sort; each sort product enhances it in some way for their own purposes, It appears to me you tried to use the DFSORT "extended parameter list."

One minor hint: the control statements pointed to by either parameter list should have a blank at the end. Your SORT statement does not have a blank, but that didn't seem to bother DFSORT.

It's been 6 or 7 years since I did a sort call from a program, and then I simulated a JCL call, and probably 30 years since I did a full dynamic call to use E15 and E35 exits. The E35 exit in that program was the major report function in the program. As I recall, there was report code after sort completed, but the major portion of the report output was done in the E35 exit.

by **sensuixel** » Wed Jul 25, 2012 12:10 pm

Both of you have guessed where my mistake was.

I have removed the OPEN/CLOSE SORTOUT from my code (assuming that it was somehow made by SORT as Dick Scherrer said) and it
works, my SORTOUT file is now populated.

Thanks you really much for your help

by **steve-myers** » Wed Jul 25, 2012 7:32 pm

sensuixel wrote:Both of you have guessed where my mistake was. ...

You're welcome,

I don't know about Mr. Scherrer, but there was no guessing involved, just a basic knowledge of how things work. When you open, then close a dataset without writing anything to the dataset as your code did, data management writes what amounts to an EOF to the dataset. This effectively destroys anything in the dataset. In fact, had SORTOUT been a tape dataset rather than a disk dataset, sort would have gotten some sort of Sx13 ABEND when it tried to open the dataset because you cannot have two open datasets on tape at the same time.

by **dick scherrer** » Wed Jul 25, 2012 7:41 pm

Nope - not a guess here either.

Looking at the code made me say "Hmmm - that's not gonna work".

d

by **BillyBoyo** » Wed Jul 25, 2012 11:08 pm

Just in case there is any confusion arising.

Chapter 4 of the DFSORT Application Programming Guide covers the requirements for your programs to be called by DFSORT as one of several "exits".

Chapter 6 of the same manual covers calling DFSORT from a program, concentrating on the requirements for Assembler as for Cobol and PL/I it is covered in their appropriate manuals.

Nowhere does it suggest that you should open SORTIN or SORTOUT. How you opened SORTIN and DFSORT successfully opened SORTIN and correctly processed the file, I don't know.

by **steve-myers** » Thu Jul 26, 2012 1:20 am

BillyBoyo wrote:... How you opened SORTIN and DFSORT successfully opened SORTIN and correctly processed the file, I don't know.

It was SORTOUT, not SORTIN.

Since there were two DCBs involved, the system treats each DCB as a separate entity. What he did was roughly comparable to this -

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OPEN (DCB1,OUTPUT)
OPEN (DCB2,OUTPUT)
PUT DCB2,RECORD
CLOSE DCB2
CLOSE DCB1
...
DCB1 DCB DSORG=PS,MACRF=PM,DDNAME=SORTOUT
DCB2 DCB DSORG=PS,MACRF=PM,DDNAME=SORTOUT

This won't work if the DD is assigned to tape; the second OPEN will get some sort of Sx13 ABEND.

by **BillyBoyo** » Thu Jul 26, 2012 5:01 am

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ASMSRCT2 CSECT
INITL 12,EQU=R BASE REG = 12, R15 = 15
OPEN_FIC EQU *
OPEN (SORTIN,(INPUT))
OPEN (SORTOUT,(OUTPUT))
LA R1,PARLST LOAD ADDR OF PARAM POINTER IN R1
LINK EP=SORT
ENDFIC CLOSE SORTIN
CLOSE SORTOUT

It was the above that "threw" me :-)

sensuixel,

This is the latest DFSORT Application Programming Guide (ice1ca60), if your DFSORT is up-to-date.

by **steve-myers** » Thu Jul 26, 2012 10:22 am

The SORTIN use was immaterial. It is not that uncommon for a program to have 2 DCBs open for the same dataset.

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