The classic approach is TRT, which is a little bit of a PITA (R2 anyone?) but 
does the job. It is a single machine instruction but that does not mean it's 
fast!

There is a new instruction (new relative to a lot of us LOL) "search string" 
(as I recall) that is more straightforward and might be faster. Again, 
fundamentally a loop whether you code it or the machine does it under the 
covers, so not as fast as you might guess. Faster than a CLI/JE loop I would 
guess.

Watch out for the "no second qualifier" special case. FOOBAR is a valid dataset 
name.

Charles

-----Original Message-----
From: IBM Mainframe Discussion List [mailto:[email protected]] On Behalf 
Of Pinnacle
Sent: Friday, March 13, 2015 10:28 AM
To: [email protected]
Subject: Need assembler trick to quickly get second and third DS qualifiers

I have a dataset FIRST.SECOND.THIRD, and I want to get SECOND.THIRD.  
Normally I would loop to one character at a time to get to the '.', but I need 
performance here.  I sure some of you assembler gurus could give me some 
inscrutable assembler to get there in like one or two instructions.  Thanks in 
advance!

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