source: trunk/minix/kernel/ipc.h@ 20

#ifndef IPC_H
#define IPC_H

/* This header file defines constants for MINIX inter-process communication.
 * These definitions are used in the file proc.c.
 */
#include <minix/com.h>

/* Masks and flags for system calls. */
#define SYSCALL_FUNC    0x000F  /* mask for system call function */
#define SYSCALL_FLAGS   0x00F0  /* mask for system call flags */
#define NON_BLOCKING    0x0010  /* do not block if target not ready */

/* System call numbers that are passed when trapping to the kernel. The 
 * numbers are carefully defined so that it can easily be seen (based on 
 * the bits that are on) which checks should be done in sys_call().
 */
#define SEND               1    /* 0001 : blocking send */
#define RECEIVE            2    /* 0010 : blocking receive */
#define SENDREC            3    /* 0011 : SEND + RECEIVE */
#define NOTIFY             4    /* 0100 : nonblocking notify */
#define ECHO               8    /* 1000 : echo a message */

#define IPC_REQUEST        5    /* 0101 : blocking request */
#define IPC_REPLY          6    /* 0110 : nonblocking reply */
#define IPC_NOTIFY         7    /* 0111 : nonblocking notification */
#define IPC_RECEIVE        9    /* 1001 : blocking receive */

/* The following bit masks determine what checks that should be done. */
#define CHECK_PTR       0xBB    /* 1011 1011 : validate message buffer */
#define CHECK_DST       0x55    /* 0101 0101 : validate message destination */
#define CHECK_DEADLOCK  0x93    /* 1001 0011 : check for deadlock */

#endif /* IPC_H */