Tandy 1000 Programmer's Reference Manual page 126

Chapter 1 I System Calls
Dealloc
Free Allocated Memory
Function Call 49H
Returns to the system pool a piece of memory that was allocated
by the Allocate Memory function call (48H).
Entry Conditions:
AH
=
49H
ES
=
segment address of memory area to be freed
Exit Conditions:
Carry set:
AX
=
error code
Carry not set:
No error.
Error Returns:
AX
=
9
Invalid block. The block passed in
ES
is not one allo-
cated via the Allocate Memory function call (48H).
Arena trashed. The internal consistency of the memory
arena has been destroyed. This is due to a user pro-
gram changing memory that does not belong to it.
AX
=
7
Example:
D e a l l o c e q "
49H
mov
e s ,
b l o c k
m o v
ah, D e a l l o c
i n t
21 H
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