Page of GC20-1807-7 As Updated April 1, 1981 by TNL GN25-0829 SUBCODE X'0014' Rx start address of virtual fullpage buffer
Ry = virtual spool reader address
The specified device is checked for an active file. If no active file
is found, cc=2 is set. otherwise, the VSPLCTL pointers are reset to the
beqinning of the file. SUBCODE X'0018' Rx start address of virtual fullpage buffer Ry virtual spool reader address
The specified device is checked for an active file. If no active file
is found, cc=2 is set. Otherwise, the file is backspaced one record and
the. record is given to the user as in subcode X'OOOO'. If the file is
already positioned at the first record, the first record is given to the
user. SUBCODE x'001C' Rx = virtual address of a 13-doubleword buffer
Ry = virtual spool reader address
Processing is the same as Subcode X'0008', except
spool files, as identified by the flag is
handled. SUBCODE x'0020' Rx = start address of fullpage virtual buffer
Ry virtual spool reader address
Processing is the same as Subcode X'OOOO', except
spool files, as identified by the SFBMON flag in
handled.
that only monitor
SFBFLAG2, can be
that only monitor SFBFLAG2, can be
Part 2. Control Program (CP) 189

Page of GC20-1S07-7 As Updated April 1, 19S1 by TNL GN25-0S29 SU BCODE X' OFFF' Rx virtual address of a 252-byte buffer
Ry spool file ID number
If Ry is nonzero, the spool input chain is searched for a file with a matchinq ID number: nOne is found or if one is found that is owned
by a different virtual machine, cc=2 is set. The chain search is
continued from the file that was found, or from the anchor if Ry is
zero, for the next file owned by the caller, independent of file type,
class, INUSE flag, etc. If none is found, cc=1 is set. Otherwise, the SFBLOK and the first record of the file (generally, the TAG) are copied
to the caller's virtual storage buffer. DIAGNOSE Code X'18' --Standard DASD I/O Input/output operations to a direct access device, of the type used by CMS, can be performed from a virtual machine using DIAGNOSE Code X'lS'. No I/O interrupts are returned by CP to the virtual machine; the DIAGNOSE instruction is completed only when the READ or WRITE commands
associated with the DIAGNOSE are completed. The Rx register contains
the virtual device address of the direct access device. The Ry register
contains the address of a chain of CCWs. The CCW chain must be in a
standard format that CP expects when DIAGNOSE Code X'1S' is used, as
shown below. DIAGNOSE must not be used to read or write
record-overflow-formatted data. Register 15 must be loaded by the user
with the number of READS or WRITEs in the CCW chain.
A typical CCW string to read or write two SOO-byte records is as
follows:
SEEK,A,CC,6 SET SECTOR (not used for 2314/2319)
SRCH,A+2,CC,5 TIC,*-S,O,O RD or WRT,DATA,CC+SILI,SOO SEEK HEAD,B,CC,6 (omitted if HEAD number unchanged) SET SECTOR SRCH,B+2,CC,5 TIC,*-S,O,O RD or WRT,DATA+SOO,SILI,SOO A SEEK and SRCH arguments for first RD/WRT B SEEK and SRCH arguments for second RD/WRT The condition codes and completion codes returned are as follows: cc=O I/O complete with no errors
cc=1 Error condition. Register 15 contains one of the following:
R15=1
R1S=2
R15=3
R15=4
R15=5
Device not attached
Device not 2319, 2314, 3330, 3340, or 3350 Attempt to write on a read-only disk
Cylinder number not in range of user's disk
virtual device is busy or has an interrupt pending 190 IBM VM/370 System programmer's Guide