Dynamic Arrays?!

 BBS: Inland Empire Archive
Date: 05-14-92 (07:54)             Number: 129
From: DAVE CLEARY                  Refer#: NONE
  To: MATT HART                     Recvd: NO  
Subj: Dynamic Arrays?!               Conf: (2) Quik_Bas
In a message of <12 May 92 00:06:00>, Matt Hart (1:170/600) writes:

 >The starting point - VARSEG and VARPTR (S1(0)) should NOT change.
 >Garbage collection is done with near memory.  I've used dynamic
 >allocation of fixed string arrays and integer arrays, kept the starting
 >address of the array ONCE in a variable so that it doesn't have to
 >re-figure it (saves time in a very graphics intensive routine) and pass
 >that stuff to an assembler routine that bit shifts and scales and finally
 >prints on the screen.  It's never tried to move those starting address.
 >Garbage collections is STILL done in current MS BASIC compilers, but, as
 >always, only on dgroup.

Garbage collection is done on far memory and dynamic arrays. For instance,
say you are allocating and deallocating many dynamic
arrays. After a while, far memory will be fragmented. If QB
did not do a garbage collection, You could end up with alot
of useless memory. I do not know what triggers it. It might
be when QB can not allocate an array because of memory
fragmentation, or it might be more often than that.

Later           Dave

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