rt/mqueue.h

   1 /* Copyright (C) 2004, 2005, 2007, 2012 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Lesser General Public
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library; if not, see
  16    <http://www.gnu.org/licenses/>.  */
  17
  18 #ifndef _MQUEUE_H
  19 #define _MQUEUE_H       1
  20
  21 #include <features.h>
  22 #include <sys/types.h>
  23 #include <fcntl.h>
  24 #define __need_sigevent_t
  25 #include <bits/siginfo.h>
  26 #define __need_timespec
  27 #include <time.h>
  28 /* Get the definition of mqd_t and struct mq_attr.  */
  29 #include <bits/mqueue.h>
  30
  31 __BEGIN_DECLS
  32
  33 /* Establish connection between a process and a message queue NAME and
  34    return message queue descriptor or (mqd_t) -1 on error.  OFLAG determines
  35    the type of access used.  If O_CREAT is on OFLAG, the third argument is
  36    taken as a `mode_t', the mode of the created message queue, and the fourth
  37    argument is taken as `struct mq_attr *', pointer to message queue
  38    attributes.  If the fourth argument is NULL, default attributes are
  39    used.  */
  40 extern mqd_t mq_open (const char *__name, int __oflag, ...)
  41   __THROW __nonnull ((1));
  42
  43 /* Removes the association between message queue descriptor MQDES and its
  44    message queue.  */
  45 extern int mq_close (mqd_t __mqdes) __THROW;
  46
  47 /* Query status and attributes of message queue MQDES.  */
  48 extern int mq_getattr (mqd_t __mqdes, struct mq_attr *__mqstat)
  49   __THROW __nonnull ((2));
  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)
  56   __THROW __nonnull ((2));
  57
  58 /* Remove message queue named NAME.  */
  59 extern int mq_unlink (const char *__name) __THROW __nonnull ((1));
  60
  61 /* Register notification issued upon message arrival to an empty
  62    message queue MQDES.  */
  63 extern int mq_notify (mqd_t __mqdes, const struct sigevent *__notification)
  64      __THROW;
  65
  66 /* Receive the oldest from highest priority messages in message queue
  67    MQDES.  */
  68 extern ssize_t mq_receive (mqd_t __mqdes, char *__msg_ptr, size_t __msg_len,
  69                            unsigned int *__msg_prio) __nonnull ((2));
  70
  71 /* Add message pointed by MSG_PTR to message queue MQDES.  */
  72 extern int mq_send (mqd_t __mqdes, const char *__msg_ptr, size_t __msg_len,
  73                     unsigned int __msg_prio) __nonnull ((2));
  74
  75 #ifdef __USE_XOPEN2K
  76 /* Receive the oldest from highest priority messages in message queue
  77    MQDES, stop waiting if ABS_TIMEOUT expires.  */
  78 extern ssize_t mq_timedreceive (mqd_t __mqdes, char *__restrict __msg_ptr,
  79                                 size_t __msg_len,
  80                                 unsigned int *__restrict __msg_prio,
  81                                 const struct timespec *__restrict __abs_timeout)
  82   __nonnull ((2, 5));
  83
  84 /* Add message pointed by MSG_PTR to message queue MQDES, stop blocking
  85    on full message queue if ABS_TIMEOUT expires.  */
  86 extern int mq_timedsend (mqd_t __mqdes, const char *__msg_ptr,
  87                          size_t __msg_len, unsigned int __msg_prio,
  88                          const struct timespec *__abs_timeout)
  89   __nonnull ((2, 5));
  90 #endif
  91
  92 /* Define some inlines helping to catch common problems.  */
  93 #if __USE_FORTIFY_LEVEL > 0 && defined __fortify_function \
  94     && defined __va_arg_pack_len
  95 # include <bits/mqueue2.h>
  96 #endif
  97
  98 __END_DECLS
  99
 100 #endif /* mqueue.h */