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Instructions Within a DSECT

 
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Pankaj Shrivastava
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PostPosted: Fri Jul 24, 2009 7:03 pm    Post subject: Instructions Within a DSECT
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Hi ,

Can we define an instruction within a DSECT , Like

ABC DSECT

SR R,R
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Bill O'Boyle

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PostPosted: Fri Jul 24, 2009 7:13 pm    Post subject: Reply to: Instructions Within a DSECT
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A DSECT is referred to as a "DUMMY SECTION" and takes up no storage until addressability has been established. After that, you can issue instructions related to this DSECT.

IE: ABC DSECT
USING *,Rx INFORM ASSEMBLER

Rx (x usually represents 2-12) is the register which contains the storage-address which maps to the DSECT. Unless you know what you're doing, stay away from R0, R1, R13, R14 and R15 as a DSECT base-register.

A COBOL LINKAGE SECTION "01" level is similar to a DSECT, for example, like DFHCOMMAREA in CICS.

COBOL automatically maps the storage (establishes addressability) to DFHCOMMAREA when EIBCALEN is greater than ZERO.

Otherwise, there's no addressability.

Bill
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Pankaj Shrivastava
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PostPosted: Fri Jul 24, 2009 9:44 pm    Post subject:
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Thx Bill for explaining in detail .
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Robert Sample

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PostPosted: Fri Jul 24, 2009 11:02 pm    Post subject:
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One of the notes in the HLASM Language Reference manual on DSECT specifically states
Quote:
1. The assembler language statements that appear in a dummy section are not assembled into object code.
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