Int 21/AX=4B80h

AX = 4B80h
DS:DX -> ASCIZ name of program to EXEC
ES = segment of PSP for kernel file

Return:
Only if call failed

Note: DR DOS uses this call after an AX=4B01h to load the kernel file into memory and patch the program's parent-PSP field to point at itself

See Also: AH=4Bh"EXEC"