Atari ST series Technical Reference Manual page 287

Replace Standard File Handle
Fforce()
P e r m i t s y o u to r e d i r e c t I /O f r o m a s t a n d a r d d e v i c e h a n d l e t o a u s e r - d e s i g ­
n a t e d o n e .
C macro format
w o r d s t a t u s , s t a n d a r d , u s e r ;
s t a t u s = F f o r c e ( s t a n d a r d , u s e r ) ;
Machine language format
m o v e . w u s e r , - ( s p )
m o v e . w
s t a n d a r d , - (s p )
m o v e . w
# $ 4 6 , - ( s p )
#1
t r a p
a d d q .l # 6 , s p
Inputs
u s e r
w o r d
s t a n d a r d
w o r d
Results
DO s t a t u s
w o r d
See also
F d u p ( )
Fforce
T h e h a n d l e o f t h e u s e r - d e s i g n a t e d file
t h a t r e p l a c e s t h e s t a n d a r d file ,
T h e h a n d l e o f t h e s t a n d a r d file t o b e r e ­
p l a c e d .
A 0 i n d i c a t e s s u c c e s s , o t h e r w i s e a n e g a t i v e G E M ­
D O S e r r o r n u m b e r is r e t u r n e d .
Opcode = 70 ($46)
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