Mainframe, MVS and zOS Discussion

I see some examples of conditional compilation, such as:

https://supportline.microfocus.com/documentation/books/opli80/pfmcro.htm

%IF A = 'CONTROL_1'
%THEN %DO;
RES = B + F(X);
%END;
%ELSE %DO;
RES = B - F(X) + SQRT(X);
LST = F(X) + 1;
%END;

However, it isn't clear to me that there is any ...

I see that PL/I has macros. For example:

%DCL RECSZ FIXED;
%RECSZ = 80;
%ACTIVATE RECSZ;

Does it also have a C like 'if defined' or ifdef like construct that I could use to conditionally compile code in two different ways?

Akatsukami wrote: Tue Oct 03, 2017 6:37 pm It's been a couple of decades since I wrote any C, so I may not properly understand what you're looking for, but I think you want the LOCATION function.

Thank you, that looks like the PL/I equivalent to C's offsetof().

The SIZE (or STG, or STORAGE) builtin function appears to be the PL/I equivalent of the C sizeof() builtin.

If I have a PL/I structure, such as:

DCL 1 MYSTRUCT,
5 F1 CHAR(13),
5 F2 FIXED BIN(31),
5 F3 FIXED DECIMAL(5,2),
5 F4 FIXED BIN(15),
5 F5 POINTER,
5 F6 CHAR(7);

Is there a way to do ...

fyi. All the calls to IEBCOPY that I'd seen specified a SELECT MEMBER clause in the command sequence. If that is omitted, the whole PDS is copied.

I see in the IDCAMS documentation that REPRO can only be used to copy a PDS member, and not the whole PDS.

Since I had a fairly small set of members in this case I used:

//CREATEPO EXEC PGM=IEFBR14
//PDSDD DD DISP=(NEW,CATLG),DSN=PJOOT.PDS,
// SPACE=(TRK,(45,15,50)),
// DCB=(RECFM=U,LRECL=80 ...

I have test results containing SYSPRINT for a regression test suite that have been copied to unix and had the ASA control characters stripped out. I'm recompiling the (PL/I) code and want to compare the results against the previous versions, but the SYSPRINT of my new PL/I programs (which I am ...

Akatsukami wrote: The Language Reference does not state that KEYTO can be used with WRITE, but rather with READ; see page 299.

On page 313, the syntax diagram shows:

►► WRITE FILE (file-reference) FROM (reference) ►
►
KEYFROM(expression)
KEYTO(reference)

I understand the point of the KEYFROM option in WRITE. For example I could do a VSAM write using:

WRITE FILE(myfile) KEYFROM(mykey) FROM(myrecord)

The Enterprise PL/I for z/OS Language Reference manual also specifies that a KEYTO() option is allowed for WRITE. What would that be used for?

I've seen two EXEC syntax variations, one with PGM=, like:

//PLUPDAT EXEC PGM=KUPDATE

(with and without PARM=), and recently also saw:

//ALLOC0 EXEC ALCPS,LLQ=SYSOUT.ACT,RF=FBA,RL=121

This form appears to pass arguments without using PARM and also doesn't specify the PGM= part of the statement ...

C doesn't have anything but errno for fopen failures, but it also doesn't have all the complex mode string extensions that exist in mainframe C.

On the mainframe, if an fopen("dd:...", modestring) fails due to a fopen mode string mismatch relative to the JCL that cataloged and/or allocated the ...

Thanks. From the link you posted, it looks like a STEP that runs BPXBATCH is the way to do it.

I'm able to use JCL and IDCAMS to populate a USS file:


//PATH JOB
//CREATE EXEC PGM=IDCAMS
//UNIX DD PATH='unixfile',PATHOPTS=(OWRONLY,OCREAT,OTRUNC),
// PATHMODE=SIRWXU
//JUNK DD DATA,DLM=@@
a
quick
brown
fox
@@
REPRO -
INFILE(JUNK) -
OUTFILE(UNIX)
/*
//SYSPRINT DD SYSOUT=*
//SYSOUT DD ...

If I allocate a DATASET in JCL, either manually, or with IDCAMS, such as:

//VSAMCR JOB
//DEFINE EXEC PGM=IDCAMS
//SYSPRINT DD SYSOUT=*
//SYSOUT DD SYSOUT=*
//SYSTERM DD SYSOUT=*
//SYSIN DD *
DEFINE CLUSTER (NAME(PJVSAM00.00000000) -
CYLINDERS(1) VOLUMES(LZ0000) -
INDEXED KEYS(10 179 ...

I'm a systems programmer with lots of experience on Unix and Windows, but am now working on the LzLabs Software Defined Mainframe. I joined this forum to help understand about JCL, mainframe file formats, z/OS assembly parameter passing conventions, and other mainframe concepts.