Atari ST series - Page 291

Mshrink
Shrink Memory Block
Mshrink()
Opcode = 74 ($4A)
W h e n a p ro g ram is ru n , it is allo cate d all th e sy ste m 's free m e m o ry . T h is
fu n ctio n is u sed to re tu rn a n y ex ce ss m e m o ry ba ck to th e sy stem .
C macro format
in t sta tu s;
lo n g a d d re ss, size ;
statu s = M sh rin k (0, a d d res s, siz e);
Machine language format
m o v e .l siz e, - (sp)
m o v e .l a d d re ss , - (sp )
m o v e .w # $ 4 A , - (sp )
tra p # 1
a d d .l # 1 0 ,sp
N o te th at a z ero w o rd m u st also b e p ass ed , as a p lace h o ld er.
Results
DO statu s w o rd A 0 sign als su cce ss, failure resu lts in a n e ga tive
G E M D O S e rro r n u m b er.
See also
M a ll o c()
Inputs
size
a d d re ss
lo n g
lo n g
T h e n u m b er o f b yte s to re tain .
T h e sta rtin g a d d re ss o f th e m em ory block
to re tain .
283