Assembling under z/OS

The minimum amount of virtual storage required by High Level Assembler is 750K bytes. 550K bytes of storage are required for High Level Assembler load modules. The rest of the storage allocated to the assembler is used for assembler working storage.

At assembly time, and during subsequent link-editing, High Level Assembler requires associated devices for the following types of input and output:
  • Source program input
  • Options file
  • Printed listing
  • Object module in relocatable card-image format, or the new object-file format
  • Terminal output
  • ADATA output
Table 1 shows the DDNAME and allowed device types associated with a particular class of assembler input or output:
Table 1. Assembler input/output devices (z/OS)
Function DDNAME Device type When required
Input SYSIN DASD
Magnetic tape
Card reader
Always 1
Macro library SYSLIB DASD When a library macro is called or a COPY statement used 1
Options file ASMAOPT DASD When assembler options are to be provided via an external file
Print SYSPRINT DASD
Magnetic tape
Printer
When the LIST assembler option is specified 1
Output to linkage editor SYSLIN DASD
Magnetic tape
When the OBJECT assembler option or the XOBJECT assembler option is specified 1
Output to linkage editor (card deck) SYSPUNCH DASD
Magnetic tape
Card punch
When the DECK assembler option is specified 1
Display SYSTERM DASD
Magnetic tape
TerminalPrinter
When the TERM assembler option is specified 1
Assembler language program data SYSADATA DASD
Magnetic tape
When the ADATA assembler option is specified 1
Note:
  1. You can specify a user-supplied exit in place of this device. For more information about the EXIT option, see Assembler options.