Atari ST series Technical Reference Manual page 279

Fopen()
O p e n s a s p e c if ie d f ile , a n d r e t u r n s a 1 6 - b i t h a n d l e t h a t c a n b e u s e d f o r
f u r t h e r a c c e s s to t h e file .
C macro format
c h a r * f n a m e ;
in t h a n d l e , m o d e ;
h a n d l e = F o p e n ( f n a m e , m o d e ) ;
Machine language format
m o v e . w # m o d e , - (s p )
m o v e .l f n a m e , - (s p )
m o v e . w # $ 3 D , - ( s p )
# 1
t r a p
# 8 , s p
a d d q .l
Inputs
m o d e w o r d
f n a m e l o n g
Results
DO h a n d l e w o r d
See also
F c r e a t e ( ) , F c l o s e ( )
Fopen
Open File
A f la g t h a t s p e c if ie s w h i c h o p e r a t i o n s w ill
b e a v a i la b l e o n c e t h e file h a s b e e n
o p e n e d .
0 =
2 =
3 =
A p o i n t e r t o a n u l l - t e r m i n a t e d A S C I I
s t r i n g c o n t a i n i n g th e n a m e o f t h e file to
o p e n .
If t h e f u n c t i o n s u c c e e d s , a 1 6 -b it h a n d l e v a l u e . If
n o t , 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 .
Opcode = 61 ($3D)
R e a d o n ly
W r i t e o n ly
R e a d o r W r i t e
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