Input Output
REG 1 1---. Parameter
List of
optional
fileid from
the com­ mand line
Initialize. ======>1 2 Define files.
3 Determine source of control card
parameters.
REG 1
Control
Parameters 1--'---1 -> '11r==>1 -2-J I 4 Construct parameter list and
control card file. hr I 5 Handle special requests. I 6 Uok to DSNS EREP (lFeEREP1 Jrib I I B Data from ur error recording 1 __ CY_linders ---II 7 Trap EXCPs to SYS1.LOGREC I issued by OS/VS EREP. Simulate n EXCP operation calling on n DMSREA to supply data from VM/370 error recording cylinders. i Notes Module Label Ref Notes
1 The initialization procedures include: DMSIFC DMSIFC Diagram CLEARF parameter (determines • Standard linkage and addressability
11-1
functions. • Loading and resolving VCONs in OS/VS EREP decks. • Loading DMSREA. • Turning off flag in CMS nucleus to
cause OS simulation. • Setting COMPSWT in CMS nucleus
to load LINK and LOAD macros
validity by examining processor
identity. If not 3031,3032, or 3033 processor reject command
but if valid, erase error records
from the error recording cylinders
then initialize SRF frames to the
beginning of the error recording
cylinders.) • CLEAR parameter.
to be entered in TEXT files. • TERMINAL parameter (stops • Establishing handling of SVC 76, SVC 18, and SVC O. reading from control file on disk
and goes to terminal to read addition-
al control parameters) . ., liivoke FILEDEF to define: 1< • Printer file (EREPPT). I INDRWD'S. • SYSIN file (SYSIN). RDYACC • Dummy file for SYS1.LOGREC RDYHIST (SERLOG). OPER12 • Error file (TOURIST). • Work file (DIRECTWK). • Accumulation tape fi Ie (ACCD EV). • SHARE parameter. • CTLCRD parameter. • ACC parameter. • HIST parameter. • MERGE parameter. • MES and THRESHOLD parameters. • RDESUM parameter. • ZERO parameter. • History input tape (ACCIN). 6 Load the address of the word that
3 Determine where control parameters HAVETYPE are to be taken from (Control file NOEXTRA points to the OS PARM list built for OS/VS EREP and LINK to IFCEREP1. or terminal). BADATTR GOODATTR 7 EXCP SVCs from EREP are inter-
cepted and simulated so they appear
4 Set up to read parameters. Obtain Diagram
storage for OS PARM list to be passed 11-1
to EREP. Read control parameters, PARMWORI< generating the OS PARM list and a RDERR1 SYSIN file as output. Call subroutine PLiSTBLD to access a SYS1. LOG R EC data set. Simulation causes calls to DMSREA for VM/370 error records. BLDL SVCs from EREP are also trapped and
simulated by DMSIFC. to read control parameters. Handle
errors.
5 If CLEAR is specified with other WANTCLR
parameters, type an error message. CLEARRTN If CLEAR is specified properly, call
subroutine to erase error records from
the VM/370 error recording cylinders.
Subroutines handle each parameter
information:
Diagraa 11-1. DftSIFC DMSIFC826E DMSIFC023E DMSIFC070E DMSIFC002E DMSIFC007E DMSIFC831E DMSIFC104S OSPARM list for OS/VS EREP DMSIFC825E DMSiFC82S; DMSIFC829W DMSIFC832S Module Label Ref
HCLEARF
HCLEAR
HTERM HSHARE HHIST HMERGE HMES HRDESUM HZERO ::lMSIFCO DMSIFC18 Chapter 11a DftSIFC and DftSB!I--ERlP/Error Recording Interface 213

Input IREG 1 Notes Module 1 The initialization procedures include: DMSREA • Saving registers. • Setting return code to zero. • Issuing DIAGNOSE X'2C' to locate
beginning of error recording area
and number of cylinders. • Setting and checking "first time" switch_ • Checking CCBOR address passed
for validity.
Note: A CCSOR disk address is a
disk addressing format devised
solely for use in CPEREP and
resembles the commonly used CCHHR disk address. In a CCBOR the fields have the following
meanmg:
Field Meaning CC Relative cylinder within
the VM/370 error record-
ing area, for example: CC = X'OOOO' for the first
cylinder of the error
recording area.
= X '0001 , for the sec-
ond cylinder of the
error recording area.
B The number of the desired
4K block within the cyl-
inder. The first 4K block
in a cylinder is X'01'. 0 Zero. R The number of the desired
record within the 4K block.
The first record in a block
is X'01'. Diagram 11-2. DMSREA Processing Output Initialize and find error recording
area on disk.
2 Obtain block containing the
requested record, read a page and
handle errors. , T6 DMSREA830E 3 If the requested record could not
be read (I/O error) or if there is Ib no such record, continue reading
consecutive blocks until the next
record is found. Calculate its CCBOR address; this becomes the
corrected CCBOR. 4 Clean up and return to caller. Label Ref NotlS DMSREA Diagram 2 DMSREA converts the CCBOR 11-2 address to a VM/370 Control Program Internal Format address and issues a DIAGNOSE X'30' to read the block
into the buffer. If the requested block
is found, return to caller. If specified FIRSTSW cylinder is outside error recording area,
sets error code in register 15 for invalid OPER4 cylinder. If end of cylinder and
no more cylinders are available, sets register 0 to zero, indicating
end-of-file to caller; otherwise,
advance to next cylinder. If an I/O error occurs so that the block
could not be read, issue message DMSREA830E_ 3 If requested record was not found, read
next block and return first record from
this block_ If block is empty or unread- able, continue reading blocks until a
record is found or until end-of-file is reached_ Use CCBOR address of the
record found as the corrected CCBOR value to be returned to the caller. Make
register 1 point to this CCBOR address.
Note: The CCBOR record addresses
are passed back to OSIVS EREP (as a
result of the EXCP simulation) as if
they were CCHHR addresses. EREP
never notices the difference and, as a
result, EREP uses CCBOR addresses in all its I/O operations to the SYS1.LOGREC data set.
4 Restore registers (except output para-
meter registers) and return to caller.
REG 15 r&r;I Module Label OPER5 OPER7 OPER16
OPER17 OPER7 OPER9 OPER10 OPER15
214 IBM VM/370 Service Routines Prograa Logic
Ref