Parameters

return_code

Return code from IGWABWO. The return code is also returned in register 15. Return codes are explained in IGWASYS, IGWASMS, IGWABWO, IGWLSHR Return and Reason Codes. This is an output argument that must be defined as an integer.

reason_code

Reason code from IGWABWO. The reason code is also returned in register 0. Reason codes are explained in IGWASYS, IGWASMS, IGWABWO, IGWLSHR Return and Reason Codes. This is an output argument that must be defined as an integer.

prob_det

Problem determination data. See IGWASYS, IGWASMS, IGWABWO, IGWLSHR Return and Reason Codes for more information about problem determination data. This is an output argument that must be defined as a two-element array of integers.

read_write

Function indicator for this service. A caller-supplied value of 0 indicates that this is a READ-type request for the backup-while-open (BWO) data of the specified data set. A value of 1 indicates a WRITE-type request, that is, an initialization or update of the specified data set's BWO data with the supplied arguments bwo_flags, bwo_recov, and bwo_resrv. The select argument indicates which arguments are to be processed. This is a required input argument that must be defined as an integer.

dsname_length

Length, in bytes, of the data set name provided by the caller in dsname. The value can be a number from 1 to 44. This is a required input argument that must be defined as an integer.

dsname

Name of the data set that the IGWABWO service operates on. Only system-managed VSAM-type data sets are eligible to be backed up while they are open for update. The dsname specified must be the base cluster name of a VSAM data set. This is a required input argument that must be defined as EBCDIC character data of length dsname_length.

select

Indicates which of the following arguments will be processed. Arguments are specified by selecting the appropriate value. This is a required input argument.

1 to process bwo_flags
2 to process bwo_recov
3 to process bwo_flags and bwo_recov

Regardless of how many arguments are to be processed, all three fields (bwo_flags, bwo_recov, and the reserved bwo_resrv field) must be defined in your program and included in the invocation. Those not selected will receive no value in a READ-type request. The values of those not selected will be ignored in a WRITE-type request.

bwo_flags

This argument is a three-element array, whose elements correspond to the three BWO flags associated with an SMS data set. bwo_flags is an output argument for read_write=0 type requests, and a required input argument for read_write=1 type requests.

The first element is associated with flag, BWO1. 1 is on, 0 is off.
This element corresponds to flag, BWO2. 1 is on, 0 is off.
This element corresponds to flag, BWO3. 1 is on, 0 is off.

Define as a three-element array of integers.

bwo_recov

This argument is an 8-byte storage area containing the recovery timestamp associated with a data set that is eligible for BWO. bwo_recov is an output argument for read_write=0 type requests, and a required input argument for read_write=1 type requests. The format of the timestamp for CICS® VSAM data sets is as follows:

The first word contains the date in packed decimal format, 0CYYDDDF, where:
0C

is the century - 00 represents 19YY, 01 represents 20YY

YY

is the last two digits of the year

DDD

is the day of the year (Julian date)

F

is the sign (F for positive number)
The second word contains the time in packed decimal format, HHMMSSTF, where:
HH

Hours, based on a 24-hour clock

MM

Minutes

SS

Seconds

T

Tenths of a second

F

is the sign (F for positive number)

bwo_resrv

This argument is reserved for future use. While the bwo_resrv argument cannot be written or read, it must be defined in your program and included in the invocation. Define as EBCDIC character data of length 16 bytes.