Tandy 1000 Programmer's Reference Manual page 131

Chapter 1 I System Calls
Exit
Terminate a Process Function Call 4CH
Terminates the current process and transfers control to the in-
voking process. In addition, a return code may be sent. All files
open at the time are closed.
This method is preferred over all others (Interrupt 20H,
JMP 0 ) .
Entry Conditions:
AH
=
4CH
AL
=
return code
Error Returns:
None.
Example:
E x e c e q u 4CH
mov
a l , c o d e
mov
a h , E x i t
I n t
21
H
~~~
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