MSDOS - Interrupt List 21h

Microsoft recomments using INT 21/AH=4Ch for DOS 2+ execution continues at address stored in INT 22 after DOS performs whatever cleanup it needs to do

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

character is echoed to standard output