Atari ST series Technical Reference Manual page 271

Get Disk Transfer Address
Fgetdta()
This function finds the current Disk Transfer Address that points to the
buffer used for disk read operations. This buffer is used as a scratch area
for directory searches.
C macro format
char *dta;
dta = Fgetdta();
Machine language format
move. w #$2F, - (sp)
trap #1
addq.l #2,sp
Inputs
None
Results
D O dta long A pointer to the current DTA.
See also
Fsetdta(), Fsfirst(), Fsnext()
Fgetdta
Opcode = 47 ($2F)
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