HLASM Language Reference

&SYSIN_DSN System Variable Symbol
Statement 8 is the last program sectioning statement processed before
statement 9 is processed. Therefore, &SYSECT is assigned the value
MAINPROG for macro instruction OUTER1 in statement 9. MAINPROG is substituted
for &SYSECT when it appears in statement 6.
Statement 3 is the program sectioning statement processed before statement 4
is processed. Therefore, &SYSECT is assigned the value CSOUT1 for macro
instruction INNER in statement 4. CSOUT1 is substituted for &SYSECT when it
appears in statement 2.
Statement 1 is used to generate a CSECT statement for statement 4. This is
the last program sectioning statement that appears before statement 5.
Therefore, &SYSECT is assigned the value INA for macro instruction INNER in
statement 5. INA is substituted for &SYSECT when it appears in statement 2.
Statement 1 is used to generate a CSECT statement for statement 5. This is
the last program sectioning statement that appears before statement 10.
Therefore, &SYSECT is assigned the value INB for macro instruction OUTER2 in
statement 10. INB is substituted for &SYSECT when it appears in statement 7.
&SYSIN_DSN System Variable Symbol
Use &SYSIN_DSN in a macro definition to obtain the name of the data set from
which the assembler is reading the source module.
The local system variable symbol &SYSIN_DSN is assigned a read-only value each
time a macro definition is called.
If concatenated data sets are used to provide the source module,
&SYSIN_DSN has a value equal to the data set name of the data set that contains
the open code source line of the macro call statement, irrespective of the nesting
depth of the macro line containing the &SYSIN_DSN reference.
When the assembler runs on the MVS operating systems, the value of the
character string assigned to &SYSIN_DSN is always the value stored in the JFCB
for SYSIN.
When the assembler runs on the CMS component of the VM operating
systems, the value of the character string assigned to &SYSIN_DSN is determined
as follows:
Figure 67. Contents of &SYSIN_DSN on CMS
SYSIN Allocated To:
CMS file
Reader
Terminal
Labeled tape file
Contents of &SYSIN_DSN:
The 8-character filename, the
8-character filetype, and the
2-character filemode of the file, each
separated by a space
READER
TERMINAL
The data set name of the tape file
Unlabeled tape file TAPn, where n is a value from 0 to 9,
or A to F.
Chapter 7. How to Specify Macro Definitions 269