.define _send, _receive, _sendrec
.globl _send, _receive, _sendrec
| See ../h/com.h for C definitions
SEND = 1
RECEIVE = 2
BOTH = 3
SYSVEC = 32

|*========================================================================*
|                           send and receive                              *
|*========================================================================*
| send(), receive(), sendrec() all save bp, but destroy ax, bx, and cx.

_send:	mov cx,*SEND		| send(dest, ptr)
	jmp L0

_receive:
	mov cx,*RECEIVE		| receive(src, ptr)
	jmp L0

_sendrec:
	mov cx,*BOTH		| sendrec(srcdest, ptr)
	jmp L0

  L0:	push bp			| save bp
	mov bp,sp		| can't index off sp
	mov ax,4(bp)		| ax = dest-src
	mov bx,6(bp)		| bx = message pointer
	int SYSVEC		| trap to the kernel
	pop bp			| restore bp
	ret			| return