;--------------------------------------------------------
;program title:         Memory Available
;author:                Peter Grogono
;date written:          May 1982
;source:                Pascal/Z Users' Group newsletter
;                       May 1982 issue.
;
;DECLARE:
;       FUNCTION MEMAVAIL: INTEGER; EXTERNAL;
;
;EXAMPLE CALL:
;       if ( memavail >= 0 ) and ( memavail < 250 ) then
;               <execute short of space routine>
;       else
;               <enough space>;
;
;SUMMARY:
;Returns the difference in value between the top of the heap and the
;stack as an integer value.  If the value returned is greater than
;32767, Pascal will consider it to be negative. You can correct for
;this by subtracting the value from 65536.  For example: assume
;memavail = -12000 then there are 65536 + (-12000) = 53536 bytes of
;unused memory.
; short program example:
;               var     free: real;
;               function memavail: integer; external;
;               ...
;               if memavail < 0 then
;                  free := 65537.0 + memavail
;               else
;                  free := memavail;
;               writeln ( free:6:0 );
;--------------------------------------------------------
       entry   memavail
       name    memavail
memavail:
       push    ix
       pop     h       ;HL = address of top of stack
       exx
       push    h
       exx
       pop     d       ;now DE = address of top of heap
       dsbc    d       ;HL = distance between heap & stack
       xchg            ;put it in DE for Pascal/Z
       ret             ;all done
;--------------------------------------------------------

You are viewing proxied material from gopher.floodgap.com. The copyright of proxied material belongs to its original authors. Any comments or complaints in relation to proxied material should be directed to the original authors of the content concerned. Please see the disclaimer for more details.