1 /* Copyright (C) 2003 Krzysztof Benedyczak & Michal Wronski 2 3 This program is free software; you can redistribute it and/or 4 modify it under the terms of the GNU Lesser General Public 5 License as published by the Free Software Foundation; either 6 version 2.1 of the License, or (at your option) any later version. 7 8 It is distributed in the hope that it will be useful, 9 but WITHOUT ANY WARRANTY; without even the implied warranty of 10 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 11 Lesser General Public License for more details. 12 13 You should have received a copy of the GNU Lesser General Public 14 License along with this software; if not, write to the Free 15 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 16 02111-1307 USA. */ 17 18 #ifndef _LINUX_MQUEUE_H 19 #define _LINUX_MQUEUE_H 20 21 #include <linux/types.h> 22 23 #define MQ_PRIO_MAX 32768 24 /* per-uid limit of kernel memory used by mqueue, in bytes */ 25 #define MQ_BYTES_MAX 819200 26 27 struct mq_attr { 28 __kernel_long_t mq_flags; /* message queue flags */ 29 __kernel_long_t mq_maxmsg; /* maximum number of messages */ 30 __kernel_long_t mq_msgsize; /* maximum message size */ 31 __kernel_long_t mq_curmsgs; /* number of messages currently queued */ 32 __kernel_long_t __reserved[4]; /* ignored for input, zeroed for output */ 33 }; 34 35 /* 36 * SIGEV_THREAD implementation: 37 * SIGEV_THREAD must be implemented in user space. If SIGEV_THREAD is passed 38 * to mq_notify, then 39 * - sigev_signo must be the file descriptor of an AF_NETLINK socket. It's not 40 * necessary that the socket is bound. 41 * - sigev_value.sival_ptr must point to a cookie that is NOTIFY_COOKIE_LEN 42 * bytes long. 43 * If the notification is triggered, then the cookie is sent to the netlink 44 * socket. The last byte of the cookie is replaced with the NOTIFY_?? codes: 45 * NOTIFY_WOKENUP if the notification got triggered, NOTIFY_REMOVED if it was 46 * removed, either due to a close() on the message queue fd or due to a 47 * mq_notify() that removed the notification. 48 */ 49 #define NOTIFY_NONE 0 50 #define NOTIFY_WOKENUP 1 51 #define NOTIFY_REMOVED 2 52 53 #define NOTIFY_COOKIE_LEN 32 54 55 #endif 56