INT 21 - European MSDOS 4.0 - "AEXEC" - EXECUTE PROGRAM IN BACKGROUND
AH = 80h
CX = mode
0000h place child in zombie mode on exit to preserve exit code
0001h discard child process and exit code on termination
DS:DX -> ASCIZ full program name
ES:BX -> parameter block (as for AX=4B00h)
Return: CF clear if successful
AX = Command Subgroup ID (CSID)
CF set on error
AX = error code (see AH=59h)
Desc:   asynchronously execute a program, creating a new process for it
Notes:  this function is called by the DETACH command
there is a system-wide limit of 32 processes
the CSID is used to identify all processes that have been spawned by
a given process, whether directly or indirectly
programs to be run in the background must use the new executable format
(see AH=4Bh)
background processes may only perform asynchronous (background) EXECs,
either this function or AX=4B04h
background processes may execute INT 11, INT 12, INT 21, INT 2A, and
INT 2F at any time; they may execute INT 10 and INT 16 only while
they have opened a popup screen via INT 2F/AX=1401h; no other
interrupts may be executed from the background
background processes may not use drive B: or overlay their code
segments
SeeAlso: AX=8700h,INT 2F/AX=1400h"POPUP"

See also: 214B

2180 - European MSDOS 4.0 - "AEXEC" - EXECUTE PROGRAM IN BACKGROUND