On Sat, 23 Jun 2007 12:29:06 -0400, Steve Myers <noone@[EMAIL PROTECTED]
>
wrote:
>SkippyPB wrote:
>> On Fri, 22 Jun 2007 17:07:32 -0400, Steve Myers <noone@[EMAIL PROTECTED]
>
>> wrote:
>>
>>> SkippyPB wrote:
>>>> On Fri, 22 Jun 2007 01:35:53 -0700, Karan <maranmeetsu@[EMAIL PROTECTED]
>
>>>> wrote:
>>>>
>>>>> Can any one give me the source for macros in assembler with
examples?
>>>> Most IBM Assembler text books can give you this information. Here's
a
>>>> simple Macro for getting the system date:
>>>>
>>>> MACRO
>>>> &LABEL GETDATE &FLD
>>>> * THE OPERAND FIELD SHOULD BE AT LEAST 4 BYTES
>>>> &LABEL TIME
>>>> MVC &FLD.(4),0(1)
>>>> MEND
>>>>
>>>> Remove nospam to email me.
>>>>
>>>> Steve
>>> Now, if it was only right. Reg 1 contains a date after TIME, not
>>> the address of the date.
>>
>> I believe it is right. The MVC would move the contents of the data
>> addressed by at 0(1) into the 4 bytes at &fld.
>>
>> Regards,
>> Remove nospam to email me.
>>
>> Steve
>
>Actually, we're both right, sort of. See
>http://publibz.boulder.ibm.com/cgi-bin/bookmgr_OS390/BOOKS/IEA2A971/75.5.5?SHELF=IEA2BK71&DT=20070126061230&CASE=
>
>According to that, the contents of reg 1 are unpredictable if
>TIME is used the way you showed.
>
>Karan, do not let the dispute between SkippyPB and me discourage
>you. Many macros are quite simple. Many of the IBM macros are
>exceedingly complex, but there are some easy ones, like, for
>example, SYS1.MACLIB(PUT).
>
>Back in the early 70s I stole something like this from Assembler
>G, and have used it ever since.
>
> MACRO
> SETR
> LCLA &A
>.LOOP AIF (&A GT 15).EXIT
>R&A EQU &A
>&A SETA &A+1
> AGO .LOOP
>.EXIT MEND
As a way of clarification, the Macro I listed was one I used on a
360/370 system and just happened to be still residing in my "toolbox".
Under 360/370 Assembler, the TIME macro places the address of the
current date in register 1. Which means the MVC instruction would
work as I described.
Regards,
////
(o o)
-oOO--(_)--OOo-
"Girls shouldn't play with men's balls.
Their hands are too small."
-- Iowa State Senator Wally Horn (addressing a
curious question: what sort of basketball
should be used by girls in Iowa schools?)
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Remove nospam to email me.
Steve
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