Choosing the name of the data space

The name you specify on the NAME parameter will identify the data space on some dump requests and IPCS commands.

Names of data spaces and hiperspaces must be unique within an address space. You have a choice of choosing the name yourself or asking the system to generate a unique name for your data space. To keep you from choosing names that it uses, MVS™ has some specific rules for you to follow. These rules are listed in the DSPSERV description under the NAME parameter in z/OS MVS Programming: Authorized Assembler Services Reference ALE-DYN.

Use the GENNAME parameter to ask the system to generate a unique name for your data space. GENNAME=YES generates a unique name that has as its last one to three characters the first one to three characters of the name you specify on the NAME parameter.

Example 1

If PAY␢␢␢␢␢ is the name you supply on the NAME parameter and you code GENNAME=YES, the system generates the following name:

nccccPAY

where the system generates the digit n and the characters cccc, and appends the characters PAY that you supplied.

Example 2

If J␢␢␢␢␢␢␢ is the name you supply on the NAME parameter and you code GENNAME=YES, the system generates the following name:

nccccJ

GENNAME=COND checks the name you supply on the NAME parameter. If it is already used for a data space or a hiperspace, DSPSERV supplies a name with the format described for the GENNAME=YES parameter. To learn the unique name that the system generates for the data space you are creating, use the OUTNAME parameter.

Note that the system has a supply of 99,999 names it can generate for data spaces and hiperspaces for a single address space. If the system tries to generate a name and finds that it has used up the supply of names, it rejects the program with a return code of "08" and a reason code of "0012". The system restores the supply of names whenever the number of such data spaces and hiperspaces owned by the address space goes to zero. Therefore, if your program is a batch job and it is creating a data space, do not:

Request that the system generate a name (through the GENNAME parameter) and
Assign ownership to a TCB that remains for the life of the address space.