rt/mqueue.h

   1 /* Copyright (C) 2004 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by Jakub Jelinek <jakub@redhat.com>, 2004.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, write to the Free
  17    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  18    02111-1307 USA.  */
  19
  20 #ifndef _MQUEUE_H
  21 #define _MQUEUE_H       1
  22
  23 #include <features.h>
  24 #include <sys/types.h>
  25 #include <fcntl.h>
  26 #define __need_sigevent_t
  27 #include <bits/siginfo.h>
  28 #define __need_timespec
  29 #include <time.h>
  30 /* Get the definition of mqd_t and struct mq_attr.  */
  31 #include <bits/mqueue.h>
  32
  33 __BEGIN_DECLS
  34
  35 /* Establish connection between a process and a message queue NAME and
  36    return message queue descriptor or (mqd_t) -1 on error.  OFLAG determines
  37    the type of access used.  If O_CREAT is on OFLAG, the third argument is
  38    taken as a `mode_t', the mode of the created message queue, and the fourth
  39    argument is taken as `struct mq_attr *', pointer to message queue
  40    attributes.  If the fourth argument is NULL, default attributes are
  41    used.  */
  42 extern mqd_t mq_open (const char *__name, int __oflag, ...) __THROW;
  43
  44 /* Removes the association between message queue descriptor MQDES and its
  45    message queue.  */
  46 extern int mq_close (mqd_t __mqdes) __THROW;
  47
  48 /* Query status and attributes of message queue MQDES.  */
  49 extern int mq_getattr (mqd_t __mqdes, struct mq_attr *__mqstat) __THROW;
  50
  51 /* Set attributes associated with message queue MQDES and if OMQSTAT is
  52    not NULL also query its old attributes.  */
  53 extern int mq_setattr (mqd_t __mqdes,
  54                        const struct mq_attr *__restrict __mqstat,
  55                        struct mq_attr *__restrict __omqstat) __THROW;
  56
  57 /* Remove message queue named NAME.  */
  58 extern int mq_unlink (const char *__name) __THROW;
  59
  60 /* Register notification upon message arrival to an empty message queue
  61    MQDES.  */
  62 extern int mq_notify (mqd_t __mqdes, const struct sigevent *__notification)
  63      __THROW;
  64
  65 /* Receive the oldest from highest priority messages in message queue
  66    MQDES.  */
  67 extern ssize_t mq_receive (mqd_t __mqdes, char *__msg_ptr, size_t __msg_len,
  68                            unsigned int *__msg_prio);
  69
  70 /* Add message pointed by MSG_PTR to message queue MQDES.  */
  71 extern int mq_send (mqd_t __mqdes, const char *__msg_ptr, size_t __msg_len,
  72                     unsigned int __msg_prio);
  73
  74 #ifdef __USE_XOPEN2K
  75 /* Receive the oldest from highest priority messages in message queue
  76    MQDES, stop waiting if ABS_TIMEOUT expires.  */
  77 extern ssize_t mq_timedreceive (mqd_t __mqdes, char *__restrict __msg_ptr,
  78                                 size_t __msg_len,
  79                                 unsigned int *__restrict __msg_prio,
  80                                 const struct timespec *__restrict __abs_timeout);
  81
  82 /* Add message pointed by MSG_PTR to message queue MQDES, stop blocking
  83    on full message queue if ABS_TIMEOUT expires.  */
  84 extern int mq_timedsend (mqd_t __mqdes, const char *__msg_ptr,
  85                          size_t __msg_len, unsigned int __msg_prio,
  86                          const struct timespec *__abs_timeout);
  87 #endif
  88
  89 __END_DECLS
  90
  91 #endif /* mqueue.h */