Your Views – DYNALLOC

I have a mainframe assembler application which is invoking Unix system
services to get the names of all of the files in an NFS-mounted folder. The
application dynamically allocates and logically concatenates these files into
one giant dataset, then uses QSAM macros to read it.
The DYNALLOC calls work this way: first, I dynamically allocate the first file in
the [...]

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CICS Shr Option (3,3)

We had an instance like the below..
A VSAM file which has got opened by a CICS program in a LPAR region needs to be copied to another LPAR region. We had given shroption (2,3) which doesnt allow us to proceed. As share option 2 allows only one processor at a time to open a data [...]

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Assign separate name for temporary dataset

There are some mainframe jobs needs to be submitted in bulk mode. There is a requirement to put the jobname in the generated temp dataset name. They all use the exact same skeleton JCL, including the same DSN=&&SB250DD1 DD statement.  This would be more helpful to avoid the ENQ conflicts
//GENER   EXEC PGM=IEBUPDTE,PARM=NEW
//SYSPRINT DD  DUMMY
//SYSUT2 [...]

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Dataset control block

The amount of virtual storage required to drive a physical I/O operation is totally dependent on access-method internal design, which is mostly outside our control.  If the desired Key field and Data field just happen to be identical to the physical Count field (a pathological case), you could surely design a channel program that could [...]

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How Data is Written to Tape

Data is written to tape in blocks.  Most tapes are “fixed block“, meaning all the blocks in a file are of a fixed size, usually an integer multiple of the record size (see Blocking Factor), but there are also “variable block” formats.  (This is not to be confused with fixed-block drives, which can only write [...]

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