Category: <b>other operating systems</b>
<p>
<pre><b>INT 15 - VMiX - "sys_sysreq" - SYSTEM CONFIGURATION MANAGER</b>

	AH = 0Bh
	STACK:	WORD	caller's UID
		DWORD	pointer to ASCIZ name of requested method
			"abort" abort current send/receive on comm port
			"block" start/end critical section
			"close" terminate interrupt-drive comm I/O
			"open" prepare comm port for interrupt-driven I/O
			"delay" set delay timer and wait
			"hibernate" put process to sleep
			"ints" enable/disable interrupt-driven INT 14h
			"length" get current send/receive buffer offsets
			"kswitch" switch stacks
			"numproc" get number of active processes
			"protocol" set protocol function for comm interrupts
			"relocate" set/reset VMiX flag for relocating to himem
			"status" get current open comm port status
			"wake" awaken a process
			"xport" get comm port polled for logins
		---if "abort"---
		 no additional arguments
		---if "block"---
		 WORD	0000h end, 0001h start
		---if "close"---
		 no additional arguments
		---if "open"---
		 WORD	comm port (00h-03h)
		 WORD	BIOS parameter byte (see <a href=../../it/00/3.html>#00300</a> at INT 14/AH=00h),
			except bits 7-5: 000 = 19200, 001 = 38400, 011 = 115200
		---if "delay"---
		 WORD	time in seconds
		---if "hibernate"---
		 WORD	process ID
		---if "ints"---
		 WORD	0000h if no, 0001h if yes
		---if "length","numproc","relocate","status","xport"---
		 no additional arguments
		---if "kswitch"---
		 DWORD	pointer to new stack
		---if "protocol"---
		 DWORD	pointer to function (must be in low "assign"ed memory
			when in 386 mode)
		---if "wake"---
		 WORD	process ID
Return: DX:AX -&gt; result or 0000h:0000h
		---if "length"---
		 BYTE	receive offset
		 BYTE	send offset
		---if "kswitch"---
		 DWORD	old stack pointer
		---if "numproc"---
		 WORD	number of active processes
		---if "status"---
		 current open comm port status
		---if "xport"---
		 current comm port being polled for logins
Note:	the "delay" command reportedly disables the keyboard until the delay
	  completes
SeeAlso: AH=05h"VMiX",AH=0Eh"VMiX"
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