1 /* Copyright (C) 2004-2022 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 <https://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 #include <bits/types/sigevent_t.h> 25 #include <bits/types/struct_timespec.h> 26 /* Get the definition of mqd_t and struct mq_attr. */ 27 #include <bits/mqueue.h> 28 29 __BEGIN_DECLS 30 31 /* Establish connection between a process and a message queue NAME and 32 return message queue descriptor or (mqd_t) -1 on error. OFLAG determines 33 the type of access used. If O_CREAT is on OFLAG, the third argument is 34 taken as a `mode_t', the mode of the created message queue, and the fourth 35 argument is taken as `struct mq_attr *', pointer to message queue 36 attributes. If the fourth argument is NULL, default attributes are 37 used. */ 38 extern mqd_t mq_open (const char *__name, int __oflag, ...) 39 __THROW __nonnull ((1)); 40 41 /* Removes the association between message queue descriptor MQDES and its 42 message queue. */ 43 extern int mq_close (mqd_t __mqdes) __THROW; 44 45 /* Query status and attributes of message queue MQDES. */ 46 extern int mq_getattr (mqd_t __mqdes, struct mq_attr *__mqstat) 47 __THROW __nonnull ((2)); 48 49 /* Set attributes associated with message queue MQDES and if OMQSTAT is 50 not NULL also query its old attributes. */ 51 extern int mq_setattr (mqd_t __mqdes, 52 const struct mq_attr *__restrict __mqstat, 53 struct mq_attr *__restrict __omqstat) 54 __THROW __nonnull ((2)); 55 56 /* Remove message queue named NAME. */ 57 extern int mq_unlink (const char *__name) __THROW __nonnull ((1)); 58 59 /* Register notification issued upon message arrival to an empty 60 message queue MQDES. */ 61 extern int mq_notify (mqd_t __mqdes, const struct sigevent *__notification) 62 __THROW; 63 64 /* Receive the oldest from highest priority messages in message queue 65 MQDES. */ 66 extern ssize_t mq_receive (mqd_t __mqdes, char *__msg_ptr, size_t __msg_len, 67 unsigned int *__msg_prio) __nonnull ((2)); 68 69 /* Add message pointed by MSG_PTR to message queue MQDES. */ 70 extern int mq_send (mqd_t __mqdes, const char *__msg_ptr, size_t __msg_len, 71 unsigned int __msg_prio) __nonnull ((2)); 72 73 #ifdef __USE_XOPEN2K 74 # ifndef __USE_TIME_BITS64 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 __nonnull ((2, 5)); 82 83 /* Add message pointed by MSG_PTR to message queue MQDES, stop blocking 84 on full message queue if ABS_TIMEOUT expires. */ 85 extern int mq_timedsend (mqd_t __mqdes, const char *__msg_ptr, 86 size_t __msg_len, unsigned int __msg_prio, 87 const struct timespec *__abs_timeout) 88 __nonnull ((2, 5)); 89 # else 90 # ifdef __REDIRECT 91 extern int __REDIRECT (mq_timedreceive, (mqd_t __mqdes, 92 char *__restrict __msg_ptr, 93 size_t __msg_len, 94 unsigned int *__restrict __msg_prio, 95 const struct timespec *__restrict __abs_timeout), 96 __mq_timedreceive_time64) 97 __nonnull ((2, 5)); 98 99 extern int __REDIRECT (mq_timedsend, (mqd_t __mqdes, 100 const char *__msg_ptr, size_t __msg_len, 101 unsigned int __msg_prio, 102 const struct timespec *__abs_timeout), 103 __mq_timedsend_time64) 104 __nonnull ((2, 5)); 105 # else 106 # define mq_timedreceive __mq_timedreceive_time64 107 # define mq_timedsend __mq_timedsend_time64 108 # endif 109 # endif 110 #endif 111 112 /* Define some inlines helping to catch common problems. */ 113 #if __USE_FORTIFY_LEVEL > 0 && defined __fortify_function \ 114 && defined __va_arg_pack_len 115 # include <bits/mqueue2.h> 116 #endif 117 118 __END_DECLS 119 120 #endif /* mqueue.h */ 121