newlib-cygwin/winsup/cygwin/include/cygwin/msg.h

103 lines
2.8 KiB
C

/* sys/msg.h
Copyright 2002 Red Hat Inc.
Written by Conrad Scott <conrad.scott@dsl.pipex.com>
This file is part of Cygwin.
This software is a copyrighted work licensed under the terms of the
Cygwin license. Please consult the file "CYGWIN_LICENSE" for
details. */
#ifndef _CYGWIN_MSG_H
#define _CYGWIN_MSG_H
#include <cygwin/ipc.h>
#ifdef __cplusplus
extern "C"
{
#endif
/* Message operation flags:
*/
#define MSG_NOERROR 0x01 /* No error if big message. */
#ifdef _KERNEL
/* Command definitions for the semctl () function:
*/
#define MSG_STAT 0x2000 /* For ipcs(8) */
#define MSG_INFO 0x2001 /* For ipcs(8) */
#endif /* _KERNEL */
/* Used for the number of messages in the message queue.
*/
typedef unsigned long msgqnum_t;
/* Used for the number of bytes allowed in a message queue.
*/
typedef unsigned long msglen_t;
struct msqid_ds
{
struct ipc_perm msg_perm; /* Operation permission structure. */
msglen_t msg_cbytes; /* Number of bytes currently on queue. */
msgqnum_t msg_qnum; /* Number of messages currently on queue. */
msglen_t msg_qbytes; /* Maximum number of bytes allowed on queue. */
pid_t msg_lspid; /* Process ID of last msgsnd (). */
pid_t msg_lrpid; /* Process ID of last msgrcv (). */
timestruc_t msg_stim; /* Time of last msgsnd (). */
timestruc_t msg_rtim; /* Time of last msgrcv (). */
timestruc_t msg_ctim; /* Time of last change. */
#ifdef _KERNEL
struct msg *msg_first;
struct msg *msg_last;
#else
long msg_spare4[2];
#endif /* _KERNEL */
};
#define msg_stime msg_stim.tv_sec
#define msg_rtime msg_rtim.tv_sec
#define msg_ctime msg_ctim.tv_sec
#ifdef _KERNEL
/* Buffer type for msgctl (IPC_INFO, ...) as used by ipcs(8).
*/
struct msginfo
{
long msgmax; /* Maximum number of bytes per
message. */
long msgmnb; /* Maximum number of bytes on any one
message queue. */
long msgmni; /* Maximum number of message queues,
system wide. */
long msgtql; /* Maximum number of messages, system
wide. */
long msgssz; /* Size of a message segment, must be
small power of 2 greater than 4. */
long msgseg; /* Number of message segments */
long msg_spare[2];
};
/* Buffer type for msgctl (MSG_INFO, ...) as used by ipcs(8).
*/
struct msg_info
{
long msg_ids; /* Number of allocated queues. */
long msg_num; /* Number of messages, system wide. */
long msg_tot; /* Size in bytes of messages, system wide. */
};
#endif /* _KERNEL */
int msgctl (int msqid, int cmd, struct msqid_ds *buf);
int msgget (key_t key, int msgflg);
ssize_t msgrcv (int msqid, void *msgp, size_t msgsz, long msgtyp, int msgflg);
int msgsnd (int msqid, const void *msgp, size_t msgsz, int msgflg);
#ifdef __cplusplus
}
#endif
#endif /* _CYGWIN_MSG_H */