Determining if Dsname is Allocated or is in the System Catalog (Entry Code X’04’)

Build the DAIR parameter block shown in Table 1 to request that DAIR determine whether the specified dsname is allocated. DAIR also searches the system catalog to find an entry for the dsname. Use the IKJDAP04 mapping macro, which is provided in SYS1.MACLIB, to map this DAIR parameter block.

Table 1. DAIR parameter block for entry code X’04’
Number of bytes	Field name	Contents or meaning
2	DA04CD	Entry code X'0004'
2	DA04FLG	A flag field set by DAIR before returning to the calling routine. The flags have the following meaning: Byte 1: `0000 0..0` Reserved. Set these bits to zero. `.... .1..` DAIR found the dsname in the catalog. `.... ..1.` The dsname is currently allocated. Byte 2: `0000 0000` Reserved. Set to zero.
2		Reserved. Set to zero.
2	DA04CTRC	These two bytes will contain an error code from the catalog management routines if an error was encountered by catalog management.
4	DA04PDSN	Place in this field the address of the dsname buffer. The dsname buffer is a 46-byte field with the following format: The first two bytes contain the length, in bytes, of the dsname; the next 44 bytes contain the dsname, left justified, and padded to the right with blanks.
1	DA04CTL	A flag field: `00.0 0000` Reserved. Set these bits to zero. `..1. ....` Prefix user ID to dsname.
2		Reserved. Set these bytes to zero.
1	DA04DSO	A flag field. These flags are set by the DAIR service routine; they describe the organization of the data set to the calling routine. These flags are returned only if the data set is currently allocated. `1... ....` Indexed sequential organization `.1.. ....` Physical sequential organization `..1. ....` Direct organization `...1 ....` BTAM or QTAM line group `.... 1...` QTAM direct access message queue `.... .1..` QTAM problem program message queue `.... ..1.` Partitioned organization `.... ...1` Unmovable

After attempting the requested function, DAIR returns, in register 15, one of the following codes: 0, 4, 8, or 52. See Return Codes from DAIR for return code meanings.