Tandy 1000 Programmer's Reference Manual page 64

Chapter
1 I System Calls
Create
Create File Function Call 16H
Searches the directory for an empty entry
or
an existing entry
for the filename in the specified FCB.
If an empty directory entry is found, it is initialized to a zero-
length file and the Open File function call (0FH) is called. You
can create a hidden file by using an extended FCB with the at-
tribute byte (offset FCB-1) set to 2.
If an entry is found for the specified filename, all data in the file
is released, making a zero-length file, and the Open File function
call (0FH) is issued for the filename. If you try to create a file
that already exists, the existing file is erased and a new, empty
file is created.
En try Conditions:
AH
=
16H
DS:DX
=
pointer to an unopened FCB for the file
Exit Conditions:
If AL
=
00H, an empty directory entry was found.
If AL
=
FFH, no empty directory entry was available
Macro Definition:
c r e a t e
m a c r o f c b
mow
d r , o f f s e t f c b
mow a h , l G H
i n t
21 H
endm
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