WAIT_UNTIL... comparison question

trustworthy

Is this:

IF( nACTION_1 = 1 ) // REPRESENTING A FLAG INSIDE A FUNCTION fnACTION_1 ()
			{
			WAIT_UNTIL ( nACTION_1 = 0 ) 'WAIT UNTIL fnACTION_1 IS COMPLETE'
			fnACTION_2 () 
			}
		    ELSE
			{
			fnACTION_2 ()
			}

Fundamentally the same as this:

IF( !nACTION_1 )
			{
			fnACTION_2 ()
			}

or, as I suspect, not.

TO CLARIFY:

In the second segment, the fnACTION_2 will fire ONLY if nACTION_1 = 0, but won't hang around until it is; I suspect it won't fire at all if nACTION_1 suddenly goes from 1 to 0, whereas the top one will. Am I right in that assumption?

Do I even make sense at this hour???

mpullin

trustworthy wrote: »

Is this:

IF( nACTION_1 = 1 ) // REPRESENTING A FLAG INSIDE A FUNCTION fnACTION_1 ()
			{
			WAIT_UNTIL ( nACTION_1 = 0 ) 'WAIT UNTIL fnACTION_1 IS COMPLETE'
			fnACTION_2 () 
			}
		    ELSE
			{
			fnACTION_2 ()
			}

Fundamentally the same as this:

IF( !nACTION_1 )
			{
			fnACTION_2 ()
			}

If nACTION_1 == 0, the two blocks do the same thing. If nACTION_1 == 1, the second block does nothing and the first block sets up a wait that executes as soon as nACTION_1 becomes 0. Incidentally, I believe the outermost IF in the first block is not necessary. Just

WAIT_UNTIL ( nACTION_1 = 0 ) fnACTION_2 ()

should do the trick as fnACTION_2 will fire right away (or at least very very soon) if nACTION_1 == 0.

trustworthy

Coolio, cheers, good tip!


The first IF in the first block is a flag inside a function that resets the whole system, so I abolutely don't want the second action to fire while thats happening. If it was a standalone statement I probably wouldnt need it but its part of a series of SELECT...ACTIVES inside a DATA_EVENT that is parsing a buffer...

I guess Im just covering all bases!


Thanks :-)

ericmedley

One little thing...

IF( !nACTION_1 )
  {
  // do something
  }

is the same as

IF(nACTION_1<>0 )
  {
  // do something
  }

Any number beside zero will trigger it.