(split) LDP man-pages の original/ を v3.32 に更新。

[linuxjm/LDP_man-pages.git] / draft / man7 / mq_overview.7

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.\" Hey Emacs! This file is -*- nroff -*- source.
.\"
.\" Copyright (C) 2006 Michael Kerrisk <mtk.manpages@gmail.com>
.\"
.\" Permission is granted to make and distribute verbatim copies of this
.\" manual provided the copyright notice and this permission notice are
.\" preserved on all copies.
.\"
.\" Permission is granted to copy and distribute modified versions of this
.\" manual under the conditions for verbatim copying, provided that the
.\" entire resulting derived work is distributed under the terms of a
.\" permission notice identical to this one.
.\"
.\" Since the Linux kernel and libraries are constantly changing, this
.\" manual page may be incorrect or out-of-date.  The author(s) assume no
.\" responsibility for errors or omissions, or for damages resulting from
.\" the use of the information contained herein.  The author(s) may not
.\" have taken the same level of care in the production of this manual,
.\" which is licensed free of charge, as they might when working
.\" professionally.
.\"
.\" Formatted or processed versions of this manual, if unaccompanied by
.\" the source, must acknowledge the copyright and authors of this work.
.\"
.\" Japanese Version Copyright (c) 2006 Akihiro MOTOKI all rights reserved.
.\" Translated 2006-03-13, Akihiro MOTOKI <amotoki@dd.iij4u.or.jp>
.\" Updated 2006-07-20, Akihiro MOTOKI <amotoki@dd.iij4u.or.jp>, LDP v2.36
.\" Updated 2009-02-23, Akihiro MOTOKI <amotoki@dd.iij4u.or.jp>, LDP v3.19
.\" Updated 2010-04-11, Akihiro MOTOKI <amotoki@dd.iij4u.or.jp>, LDP v3.24
.\"
.\"WORD:        message queue descriptor        ¥á¥Ã¥»¡¼¥¸¥­¥å¡¼µ­½Ò»Ò
.\"WORD:        message queue description       ¥á¥Ã¥»¡¼¥¸¥­¥å¡¼µ­½Ò
.\"
.TH MQ_OVERVIEW 7 2009-09-27 "Linux" "Linux Programmer's Manual"
.\"O .SH NAME
.SH ̾Á°
.\"O mq_overview \- Overview of POSIX message queues
mq_overview \- POSIX ¥á¥Ã¥»¡¼¥¸¥­¥å¡¼¤Î³µÍ×
.\"O .SH DESCRIPTION
.SH ÀâÌÀ
.\"O POSIX message queues allow processes to exchange data in
.\"O the form of messages.
.\"O This API is distinct from that provided by System V message queues
.\"O .RB ( msgget (2),
.\"O .BR msgsnd (2),
.\"O .BR msgrcv (2),
.\"O etc.), but provides similar functionality.
POSIX ¥á¥Ã¥»¡¼¥¸¥­¥å¡¼¤ò»ÈÍѤ¹¤ë¤È¡¢¥×¥í¥»¥¹´Ö¤Ç
¥á¥Ã¥»¡¼¥¸¤Î·Á¤Ç¤Î¥Ç¡¼¥¿¤Î¤ä¤ê¼è¤ê¤ò¹Ô¤¦¤³¤È¤¬¤Ç¤­¤ë¡£
¤³¤Î API ¤Ï System V ¥á¥Ã¥»¡¼¥¸¥­¥å¡¼¤Î API
.RB ( msgget (2),
.BR msgsnd (2),
.BR msgrcv (2)
¤Ê¤É) ¤È¤Ï°Û¤Ê¤ë¤â¤Î¤À¤¬¡¢Æ±Íͤε¡Ç½¤òÄ󶡤¹¤ë¡£

.\"O Message queues are created and opened using
.\"O .BR mq_open (3);
.\"O this function returns a
.\"O .I message queue descriptor
.\"O .RI ( mqd_t ),
.\"O which is used to refer to the open message queue in later calls.
.\"O Each message queue is identified by a name of the form
.\"O .IR /somename ;
.\"O that is, a null-terminated string of up to
.\"O .BI NAME_MAX
.\"O (i.e., 255) characters consisting of an initial slash,
.\"O followed by one or more characters, none of which are slashes.
¥á¥Ã¥»¡¼¥¸¥­¥å¡¼¤ÎºîÀ®¤È¥ª¡¼¥×¥ó¤Ï
.BR mq_open (3)
¤ò»È¤Ã¤Æ¹Ô¤¦¡£¤³¤Î´Ø¿ô¤Ï
.I ¥á¥Ã¥»¡¼¥¸¥­¥å¡¼µ­½Ò»Ò (message queue descriptor)
.RI ( mqd_t )
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¤ò»È¤Ã¤Æ»²¾È¤µ¤ì¤ë¡£
³Æ¥á¥Ã¥»¡¼¥¸¥­¥å¡¼¤Ï
.I /somename
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.\"O Two processes can operate on the same queue by passing the same name to
.\"O .BR mq_open (3).
.BR mq_open (3)
¤ËƱ¤¸Ì¾Á°¤òÅϤ¹¤³¤È¤Ç¡¢2¤Ä¤Î¥×¥í¥»¥¹¤ÇƱ°ì¤Î¥­¥å¡¼¤ò
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.\"O Messages are transferred to and from a queue using
.\"O .BR mq_send (3)
.\"O and
.\"O .BR mq_receive (3).
.\"O When a process has finished using the queue, it closes it using
.\"O .BR mq_close (3),
.\"O and when the queue is no longer required, it can be deleted using
.\"O .BR mq_unlink (3).
.\"O Queue attributes can be retrieved and (in some cases) modified using
.\"O .BR mq_getattr (3)
.\"O and
.\"O .BR mq_setattr (3).
.\"O A process can request asynchronous notification
.\"O of the arrival of a message on a previously empty queue using
.\"O .BR mq_notify (3).
¥á¥Ã¥»¡¼¥¸¤Î¥­¥å¡¼¤Ø¤ÎÁ÷¼õ¿®¤Ï
.BR mq_send (3)
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.BR mq_receive (3)
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.BR mq_unlink (3)
¤ò»È¤Ã¤Æ¥­¥å¡¼¤òºï½ü¤Ç¤­¤ë¡£¥­¥å¡¼¤Î°À­¤Ï
.BR mq_getattr (3)
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.BR mq_setattr (3)
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.BR mq_notify (3)
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ÄÌÃΤ¹¤ë¤è¤¦¤ËÍ׵᤹¤ë¤³¤È¤â¤Ç¤­¤ë¡£

.\"O A message queue descriptor is a reference to an
.\"O .I "open message queue description"
.\"O (cf.
.\"O .BR open (2)).
.\"O After a
.\"O .BR fork (2),
.\"O a child inherits copies of its parent's message queue descriptors,
.\"O and these descriptors refer to the same open message queue descriptions
.\"O as the corresponding descriptors in the parent.
.\"O Corresponding descriptors in the two processes share the flags
.\"O .RI ( mq_flags )
.\"O that are associated with the open message queue description.
¥á¥Ã¥»¡¼¥¸¥­¥å¡¼µ­½Ò»Ò¤Ï
.I "¥ª¡¼¥×¥ó¥á¥Ã¥»¡¼¥¸¥­¥å¡¼µ­½Ò (open message queue description)"
¤Ø¤Î»²¾È¤Ç¤¢¤ë
.RB ( open (2)
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.RI ( mq_flags )
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.\"O Each message has an associated
.\"O .IR priority ,
.\"O and messages are always delivered to the receiving process
.\"O highest priority first.
.\"O Message priorities range from 0 (low) to
.\"O .I sysconf(_SC_MQ_PRIO_MAX)\ -\ 1
.\"O (high).
.\"O On Linux,
.\"O .I sysconf(_SC_MQ_PRIO_MAX)
.\"O returns 32768, but POSIX.1-2001 only requires
.\"O an implementation to support priorities in the range 0 to 31;
.\"O some implementations only provide this range.
³Æ¥á¥Ã¥»¡¼¥¸¤Ë¤Ï¤½¤ì¤¾¤ì
.I Í¥ÀèÅÙ (priority)
¤¬¤¢¤ê¡¢¥á¥Ã¥»¡¼¥¸¤Î¼õ¿®¥×¥í¥»¥¹¤Ø¤ÎÇÛÁ÷¤Ï¾ï¤Ë
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¥á¥Ã¥»¡¼¥¸¤ÎÍ¥ÀèÅÙ¤Ï 0 (ÄãÍ¥Àè) ¤«¤é
.I sysconf(_SC_MQ_PRIO_MAX)\ -\ 1
(¹âÍ¥Àè) ¤ÎÃͤò»ý¤Ä¡£
Linux ¤Ç¤Ï¡¢
.I sysconf(_SC_MQ_PRIO_MAX)
¤Ï 32768 ¤òÊÖ¤¹¤¬¡¢
POSIX.1-2001 ¤ÇÍ׵ᤵ¤ì¤Æ¤¤¤ë¤Î¤Ï 0 ¤«¤é 31 ¤Þ¤Ç¤ÎÍ¥ÀèÅÙ¤ò
¼ÂÁõ¤¹¤ë¤³¤È¤À¤±¤Ç¤¢¤ê¡¢¼ÂÁõ¤Ë¤è¤Ã¤Æ¤Ï¤³¤ÎÈϰϤÎÍ¥ÀèÅÙ¤·¤«
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.PP
.\"O The remainder of this section describes some specific details
.\"O of the Linux implementation of POSIX message queues.
¤³¤ÎÀá¤Î»Ä¤ê¤Ç¤Ï¡¢POSIX ¥á¥Ã¥»¡¼¥¸¥­¥å¡¼¤Î Linux ¤Î¼ÂÁõ¤Î¾ÜºÙ
¤Ë¤Ä¤¤¤ÆÀâÌÀ¤¹¤ë¡£
.\"O .SS Library interfaces and system calls
.SS ¥é¥¤¥Ö¥é¥ê¥¤¥ó¥¿¥Õ¥§¡¼¥¹¤È¥·¥¹¥Æ¥à¥³¡¼¥ë
.\"O In most cases the
.\"O .B mq_*()
.\"O library interfaces listed above are implemented
.\"O on top of underlying system calls of the same name.
.\"O Deviations from this scheme are indicated in the following table:
¤Û¤È¤ó¤É¤Î¾ì¹ç¡¢¾åµ­¤Î
.B mq_*()
¥é¥¤¥Ö¥é¥ê¥¤¥ó¥¿¥Õ¥§¡¼¥¹¤Ï¡¢Æ±¤¸Ì¾Á°¤Î²¼°ÌÁؤΥ·¥¹¥Æ¥à¥³¡¼¥ë¤ò
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°Ê²¼¤Îɽ¤Ë¼¨¤¹¡£
.in +4n
.TS
lB lB
l l.
Library interface       System call
mq_close(3)     close(2)
mq_getattr(3)   mq_getsetattr(2)
mq_notify(3)    mq_notify(2)
mq_open(3)      mq_open(2)
mq_receive(3)   mq_timedreceive(2)
mq_send(3)      mq_timedsend(2)
mq_setattr(3)   mq_getsetattr(2)
mq_timedreceive(3)      mq_timedreceive(2)
mq_timedsend(3) mq_timedsend(2)
mq_unlink(3)    mq_unlink(2)
.TE
.in
.\"O .SS Versions
.SS ¥Ð¡¼¥¸¥ç¥ó
.\"O POSIX message queues have been supported on Linux since kernel 2.6.6.
.\"O Glibc support has been provided since version 2.3.4.
Linux ¤Ç¤Ï POSIX ¥á¥Ã¥»¡¼¥¸¥­¥å¡¼¤Ï¥«¡¼¥Í¥ë 2.6.6 °Ê¹ß¤Ç¥µ¥Ý¡¼¥È¤µ¤ì¤Æ¤¤¤ë¡£
glibc ¤Ç¤Ï¥Ð¡¼¥¸¥ç¥ó 2.3.4 °Ê¹ß¤Ç¥µ¥Ý¡¼¥È¤µ¤ì¤Æ¤¤¤ë¡£
.\"O .SS Kernel configuration
.SS ¥«¡¼¥Í¥ë¤ÎÀßÄê
.\"O Support for POSIX message queues is configurable via the
.\"O .B CONFIG_POSIX_MQUEUE
.\"O kernel configuration option.
.\"O This option is enabled by default.
POSIX ¥á¥Ã¥»¡¼¥¸¥­¥å¡¼¤Î¥µ¥Ý¡¼¥È¤Ï¡¢¥«¡¼¥Í¥ë¤ÎÀßÄê (configuration)
¥ª¥×¥·¥ç¥ó
.B CONFIG_POSIX_MQUEUE
¤ÇÀßÄê²Äǽ¤Ç¤¢¤ë¡£¤³¤Î¥ª¥×¥·¥ç¥ó¤Ï¥Ç¥Õ¥©¥ë¥È¤Ç¤ÏÍ­¸ú¤Ç¤¢¤ë¡£
.\"O .SS Persistence
.SS »ý³À­
.\"O POSIX message queues have kernel persistence:
.\"O if not removed by
.\"O .BR mq_unlink (3),
.\"O a message queue will exist until the system is shut down.
POSIX ¥á¥Ã¥»¡¼¥¸¥­¥å¡¼¤Ï¥«¡¼¥Í¥ëÆâ¤ÇÊÝ»ý¤µ¤ì¤ë¡£
.BR mq_unlink (3)
¤Çºï½ü¤µ¤ì¤Ê¤±¤ì¤Ð¡¢¥á¥Ã¥»¡¼¥¸¥­¥å¡¼¤Ï
¥·¥¹¥Æ¥à¤¬¥·¥ã¥Ã¥È¥À¥¦¥ó¤µ¤ì¤ë¤Þ¤Ç¸ºß¤·Â³¤±¤ë¡£
.\"O .SS Linking
.SS ¥ê¥ó¥¯
.\"O Programs using the POSIX message queue API must be compiled with
.\"O .I cc \-lrt
.\"O to link against the real-time library,
.\"O .IR librt .
POSIX ¥á¥Ã¥»¡¼¥¸¥­¥å¡¼ API ¤ò»ÈÍѤ·¤¿¥×¥í¥°¥é¥à¤Ï
.I cc \-lrt
¤Ç¥³¥ó¥Ñ¥¤¥ë¤·¡¢¥ê¥¢¥ë¥¿¥¤¥à¥é¥¤¥Ö¥é¥ê
.I librt
¤È¥ê¥ó¥¯¤·¤Ê¤±¤ì¤Ð¤Ê¤é¤Ê¤¤¡£
.\"O .SS /proc interfaces
.SS /proc ¥¤¥ó¥¿¥Õ¥§¡¼¥¹
.\"O The following interfaces can be used to limit the amount of
.\"O kernel memory consumed by POSIX message queues:
°Ê²¼¤Î¥¤¥ó¥¿¥Õ¥§¡¼¥¹¤ò»È¤Ã¤Æ¡¢POSIX ¥á¥Ã¥»¡¼¥¸¥­¥å¡¼¤¬¾ÃÈñ¤¹¤ë¥«¡¼¥Í¥ë
¥á¥â¥ê¤ÎÎ̤òÀ©¸Â¤¹¤ë¤³¤È¤¬¤Ç¤­¤ë¡£
.TP
.I /proc/sys/fs/mqueue/msg_max
.\"O This file can be used to view and change the ceiling value for the
.\"O maximum number of messages in a queue.
.\"O This value acts as a ceiling on the
.\"O .I attr\->mq_maxmsg
.\"O argument given to
.\"O .BR mq_open (3).
.\"O The default value for
.\"O .I msg_max
.\"O is 10.
.\"O The minimum value is 1 (10 in kernels before 2.6.28).
.\"O The upper limit is
.\"O .BR HARD_MAX :
.\"O .IR "(131072\ /\ sizeof(void\ *))"
.\"O (32768 on Linux/86).
.\"O This limit is ignored for privileged processes
.\"O .RB ( CAP_SYS_RESOURCE ),
.\"O but the
.\"O .B HARD_MAX
.\"O ceiling is nevertheless imposed.
¤³¤Î¥Õ¥¡¥¤¥ë¤ò»È¤Ã¤Æ¡¢°ì¤Ä¤Î¥­¥å¡¼¤ËÆþ¤ì¤é¤ì¤ë¥á¥Ã¥»¡¼¥¸¤ÎºÇÂç¿ô¤Î
¾å¸ÂÃͤò»²¾È¤·¤¿¤êÊѹ¹¤·¤¿¤ê¤Ç¤­¤ë¡£¤³¤ÎÃͤϡ¢
.BR mq_open (3)
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.I attr\->mq_maxmsg
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.I msg_max
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.TP
.I /proc/sys/fs/mqueue/msgsize_max
.\"O This file can be used to view and change the ceiling on the
.\"O maximum message size.
.\"O This value acts as a ceiling on the
.\"O .I attr\->mq_msgsize
.\"O argument given to
.\"O .BR mq_open (3).
.\"O The default value for
.\"O .I msgsize_max
.\"O is 8192 bytes.
.\"O The minimum value is 128 (8192 in kernels before 2.6.28).
.\"O The upper limit for
.\"O .I msgsize_max
.\"O is 1,048,576 (in kernels before 2.6.28, the upper limit was
.\"O .BR INT_MAX ;
.\"O that is, 2,147,483,647 on Linux/86).
.\"O This limit is ignored for privileged processes
.\"O .RB ( CAP_SYS_RESOURCE ).
¤³¤Î¥Õ¥¡¥¤¥ë¤ò»È¤Ã¤Æ¡¢¥á¥Ã¥»¡¼¥¸¤ÎºÇÂ祵¥¤¥º¤Î¾å¸ÂÃͤò  
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¤ËÅϤ¹  
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.I msgsize_max  
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(2.6.28 ¤è¤êÁ°¤Î¥«¡¼¥Í¥ë¤Ç¤Ï¡¢¾å¸Â¤Ï
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.RB ( CAP_SYS_RESOURCE )        
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.TP
.I /proc/sys/fs/mqueue/queues_max
.\"O This file can be used to view and change the system-wide limit on the
.\"O number of message queues that can be created.
.\"O Only privileged processes
.\"O .RB ( CAP_SYS_RESOURCE )
.\"O can create new message queues once this limit has been reached.
.\"O The default value for
.\"O .I queues_max
.\"O is 256; it can be changed to any value in the range 0 to INT_MAX.
¤³¤Î¥Õ¥¡¥¤¥ë¤ò»È¤Ã¤Æ¡¢ºîÀ®¤¹¤ë¤³¤È¤¬¤Ç¤­¤ë¥á¥Ã¥»¡¼¥¸¥­¥å¡¼¤Î¿ô¤Ë        
ÂФ¹¤ë¥·¥¹¥Æ¥àÁ´ÂΤǤÎÀ©¸Â¤ò»²¾È¤·¤¿¤êÊѹ¹¤·¤¿¤ê¤Ç¤­¤ë¡£        
°ìÅÙ¤³¤Î¾å¸Â¤Ë㤹¤ë¤È¡¢¿·¤·¤¤¥á¥Ã¥»¡¼¥¸¥­¥å¡¼¤òºîÀ®¤Ç¤­¤ë¤Î¤Ï  
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.\"O .SS Resource limit
.SS ¥ê¥½¡¼¥¹À©¸Â
.\"O The
.\"O .B RLIMIT_MSGQUEUE
.\"O resource limit, which places a limit on the amount of space
.\"O that can be consumed by all of the message queues
.\"O belonging to a process's real user ID, is described in
.\"O .BR getrlimit (2).
¥ê¥½¡¼¥¹¾å¸Â
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.BR getrlimit (2)
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.\"O .SS Mounting the message queue file system
.SS ¥á¥Ã¥»¡¼¥¸¥­¥å¡¼¡¦¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤Î¥Þ¥¦¥ó¥È
.\"O On Linux, message queues are created in a virtual file system.
.\"O (Other implementations may also provide such a feature,
.\"O but the details are likely to differ.)
.\"O This file system can be mounted (by the superuser) using the following
.\"O commands:
Linux ¤Ç¤Ï¡¢¥á¥Ã¥»¡¼¥¸¥­¥å¡¼¤Ï²¾ÁÛ¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥àÆâ¤ËºîÀ®¤µ¤ì¤ë
(¾¤Î¼ÂÁõ¤Ç¤âƱÍͤε¡Ç½¤¬Ä󶡤µ¤ì¤Æ¤¤¤ë¤â¤Î¤â¤¢¤ë¤¬¡¢
¾ÜºÙ¤Ï°ã¤Ã¤Æ¤¤¤ë¤À¤í¤¦)¡£
°Ê²¼¤Î¥³¥Þ¥ó¥É¤ò»È¤¦¤³¤È¤Ç (¥¹¡¼¥Ñ¡¼¥æ¡¼¥¶¤Ï)
¤³¤Î¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤ò¥Þ¥¦¥ó¥È¤Ç¤­¤ë:
.in +4n
.nf

.RB "#" " mkdir /dev/mqueue"
.RB "#" " mount \-t mqueue none /dev/mqueue"

.fi
.in
.\"O The sticky bit is automatically enabled on the mount directory.
¥Þ¥¦¥ó¥È¤·¤¿¥Ç¥£¥ì¥¯¥È¥ê¤Î¥¹¥Æ¥£¥Ã¥­¡¼¥Ó¥Ã¥È (sticky bit) ¤Ï
¼«Æ°Åª¤Ë¥ª¥ó¤È¤Ê¤ë¡£

.\"O After the file system has been mounted, the message queues on the system
.\"O can be viewed and manipulated using the commands usually used for files
.\"O (e.g.,
.\"O .BR ls (1)
.\"O and
.\"O .BR rm (1)).
¥á¥Ã¥»¡¼¥¸¥­¥å¡¼¡¦¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤Î¥Þ¥¦¥ó¥È¸å¤Ï¡¢¥Õ¥¡¥¤¥ë¤ËÂФ·¤Æ
Ä̾ï»È¤¦¥³¥Þ¥ó¥É (Î㤨¤Ð
.BR ls (1)
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.\"O The contents of each file in the directory consist of a single line
.\"O containing information about the queue:
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.RB "$" " cat /dev/mqueue/mymq"
QSIZE:129     NOTIFY:2    SIGNO:0    NOTIFY_PID:8260

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.\"O These fields are as follows:
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.B QSIZE
.\"O Number of bytes of data in all messages in the queue.
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.B NOTIFY_PID
.\"O If this is nonzero, then the process with this PID has used
.\"O .BR mq_notify (3)
.\"O to register for asynchronous message notification,
.\"O and the remaining fields describe how notification occurs.
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.BR mq_notify (3)
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.B NOTIFY
.\"O Notification method:
.\"O 0 is
.\"O .BR SIGEV_SIGNAL ;
.\"O 1 is
.\"O .BR SIGEV_NONE ;
.\"O and
.\"O 2 is
.\"O .BR SIGEV_THREAD .
ÄÌÃÎÊýË¡:
0 ¤Ï
.BR SIGEV_SIGNAL ;
1 ¤Ï
.BR SIGEV_NONE ;
2 ¤Ï
.B SIGEV_THREAD
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.B SIGNO
.\"O Signal number to be used for
.\"O .BR SIGEV_SIGNAL .
.B SIGEV_SIGNAL
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.\"O .SS Polling message queue descriptors
.SS ¥á¥Ã¥»¡¼¥¸¥­¥å¡¼µ­½Ò»Ò¤Î¥Ý¡¼¥ê¥ó¥°
.\"O On Linux, a message queue descriptor is actually a file descriptor,
.\"O and can be monitored using
.\"O .BR select (2),
.\"O .BR poll (2),
.\"O or
.\"O .BR epoll (7).
.\"O This is not portable.
Linux ¤Ç¤Ï¡¢¥á¥Ã¥»¡¼¥¸¥­¥å¡¼µ­½Ò»Ò¤Ï¼ÂºÝ¤Ï¥Õ¥¡¥¤¥ëµ­½Ò»Ò (file descriptor)
¤Ç¤¢¤ê¡¢
.BR select (2),
.BR poll (2),
.BR epoll (7)
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.\"O .SH "CONFORMING TO"
.SH ½àµò
POSIX.1-2001.
.\"O .SH NOTES
.SH Ãí°Õ
.\"O System V message queues
.\"O .RB ( msgget (2),
.\"O .BR msgsnd (2),
.\"O .BR msgrcv (2),
.\"O etc.) are an older API for exchanging messages between processes.
.\"O POSIX message queues provide a better designed interface than
.\"O System V message queues;
.\"O on the other hand POSIX message queues are less widely available
.\"O (especially on older systems) than System V message queues.
System V ¥á¥Ã¥»¡¼¥¸¥­¥å¡¼
.RB ( msgget (2),
.BR msgsnd (2),
.BR msgrcv (2)
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.\"O Linux does not currently (2.6.26) support the use of access control
.\"O lists (ACLs) for POSIX message queues.
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Linux ¤Ï POSIX ¥á¥Ã¥»¡¼¥¸¥­¥å¡¼¤ËÂФ¹¤ë¥¢¥¯¥»¥¹À©¸æ¥ê¥¹¥È (ACL) ¤Ë
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.\"O .SH EXAMPLE
.SH Îã
.\"O An example of the use of various message queue functions is shown in
.\"O .BR mq_notify (3).
³Æ¼ï¤Î¥á¥Ã¥»¡¼¥¸¥­¥å¡¼´Ø¿ô¤ò»ÈÍѤ·¤¿Î㤬
.BR mq_notify (3)
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.\"O .SH "SEE ALSO"
.SH ´ØÏ¢¹àÌÜ
.BR getrlimit (2),
.BR mq_getsetattr (2),
.BR poll (2),
.BR select (2),
.BR mq_close (3),
.BR mq_getattr (3),
.BR mq_notify (3),
.BR mq_open (3),
.BR mq_receive (3),
.BR mq_send (3),
.BR mq_unlink (3),
.BR epoll (7)