Category: <b>DOS kernel</b>
<p>
<pre><b>INT 21 - DOS 1+ - TERMINATE PROGRAM</b>

	AH = 00h
	CS = PSP segment
Notes:	Microsoft recommends using INT 21/AH=4Ch for DOS 2+
	this function sets the program's return code (ERRORLEVEL) to 00h
	execution continues at the address stored in INT 22 after DOS performs
	  whatever cleanup it needs to do (restoring the INT 22,INT 23,INT 24
	  vectors from the PSP assumed to be located at offset 0000h in the
	  segment indicated by the stack copy of CS, etc.)
	if the PSP is its own parent, the process's memory is not freed; if
	  INT 22 additionally points into the terminating program, the
	  process is effectively NOT terminated
	not supported by MS Windows 3.0 DOSX.EXE DOS extender
SeeAlso: AH=26h,AH=31h,AH=4Ch,INT 20,INT 22
</pre>