.\" Copyright 1993 Giorgio Ciucci (giorgio@crcc.it)
.\" and Copyright 2004, 2005 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.\" manual page may be incorrect or out-of-date.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.
.\"
.\" Modified Tue Oct 22 08:11:14 EDT 1996 by Eric S. Raymond <esr@thyrsus.com>
.\" Modified Sun Feb 18 01:59:29 2001 by Andries E. Brouwer <aeb@cwi.nl>
.\" Modified, 27 May 2004, Michael Kerrisk <mtk.manpages@gmail.com>
.\"     Added notes on CAP_IPC_OWNER requirement
.\" Modified, 17 Jun 2004, Michael Kerrisk <mtk.manpages@gmail.com>
.\"     Added notes on CAP_SYS_ADMIN requirement for IPC_SET and IPC_RMID
.\" Modified, 11 Nov 2004, Michael Kerrisk <mtk.manpages@gmail.com>
.\"	Language and formatting clean-ups
.\"	Added msqid_ds and ipc_perm structure definitions
.\" 2005-08-02, mtk: Added IPC_INFO, MSG_INFO, MSG_STAT descriptions
.\"
.\" Japanese Version Copyright (c) 1997 HANATAKA Shinya
.\"         all rights reserved.
.\" Translated 1997-02-23, HANATAKA Shinya <hanataka@abyss.rim.or.jp>
.\" Updated & Modified 2001-06-04, Yuichi SATO <ysato@h4.dion.ne.jp>
.\" Updated & Modified 2002-07-06, Yuichi SATO
.\" Updated & Modified 2004-12-31, Yuichi SATO <ysato444@yahoo.co.jp>
.\" Updated & Modified 2005-10-10, Akihiro MOTOKI <amotoki@dd.iij4u.or.jp>
.\"
.\"WORD:	message			å
.\"WORD:	queue			塼
.\"WORD:	member			С
.\"WORD:	structure		¤
.\"WORD:	effective user ID	¸桼 ID
.\"WORD:	creator			
.\"WORD:	owner			ͭ
.\"WORD:	feature test macro	ǽޥ
.\"
.TH MSGCTL 2 2008-08-06 "Linux" "Linux Programmer's Manual"
.SH ̾
msgctl \- å
.SH 
.nf
.B #include <sys/types.h>
.B #include <sys/ipc.h>
.B #include <sys/msg.h>

.BI "int msgctl(int " msqid ", int " cmd ", struct msqid_ds *" buf );
.fi
.SH 
.BR msgctl ()
ϥå塼̻
.I msqid
ǻꤵ줿å塼 (message queue) Ф
.I cmd
ǻꤵ줿Ԥʤ
.PP
.I msqid_ds
ǡ¤Τ \fI<sys/msg.h>\fP ǰʲΤ褦Ƥ:
.nf
.in +4n

struct msqid_ds {
    struct ipc_perm msg_perm;     /* ͭȵ */
    time_t          msg_stime;    /* Ǹ msgsnd(2) λ */
    time_t          msg_rtime;    /* Ǹ msgrcv(2) λ */
    time_t          msg_ctime;    /* ǸѹԤ줿 */
    unsigned long   __msg_cbytes; /* 塼ˤ븽ߤΥХȿ
                                     (ɸ) */
    msgqnum_t       msg_qnum;     /* 塼ˤ븽äƤ
                                     åο */
    msglen_t        msg_qbytes;   /* 塼˵ĤƤ
                                     Хȿ */
    pid_t           msg_lspid;    /* Ǹ msgsnd(2)  PID */
    pid_t           msg_lrpid;    /* Ǹ msgrcv(2)  PID */
};
.in
.fi
.PP
.I ipc_perm
¤Τ \fI<sys/ipc.h>\fP ǰʲΤ褦Ƥ
(Ĵ줿եɤ
.B IPC_SET
ȤäǽǤ):
.PP
.nf
.in +4n
struct ipc_perm {
    key_t          __key;       /* msgget(2) Ϳ륭 */
    uid_t          \fBuid\fP;         /* ͭԤμ¸ UID */
    gid_t          \fBgid\fP;         /* ͭԤμ¸ GID */
    uid_t          cuid;        /* Ԥμ¸ UID */
    gid_t          cgid;        /* Ԥμ¸ GID */
    unsigned short \fBmode\fP;        /*  */
    unsigned short __seq;       /* ֹ */
};
.in
.fi
.PP
.I cmd
Ȥͭͤ:
.TP
.B IPC_STAT
.I msqid
˴ϢŤ줿å塼ǡ¤Τ顢ݥ
.I buf
ؤ
.I msqid_ds
¤Τ˾򥳥ԡ롣
ƤӽФ¦ϥå塼Фɤ߹ߵĤäƤʤФʤʤ
.TP
.B IPC_SET
ݥ
.I buf
ؤ
.I msqid_ds
¤ΤΥСͤ򡢥å塼˴ϢŤ줿
ͥ롦ǡ¤Τ˽񤭹ߡ
.I msg_ctime
С⹹롣
¤ΤΥСΤΤʲ˼:
.IR msg_qbytes ,
.IR msg_perm.uid ,
.IR msg_perm.gid ,
.I msg_perm.mode
(β 9 ӥå)
ƤӽФץμ¸桼 ID å塼νͭ
.RI ( msg_perm.uid )
ޤϺ
.RI ( msg_perm.cuid )
Ȱפ뤫ƤӽФøʤФʤʤ
.I msg_qbytes
򥷥ƥࡦѥ᡼
.B MSGMNB
ĶꤹˤϡŬڤø (Linux Ǥ
.B CAP_IPC_RESOURCE
ѥӥƥ (capability)) ɬפǤ롣
.TP
.B IPC_RMID
å塼򤿤˺롣
Ʊˤι¤Τɤ߽񤭤Ԥ֤ˤäץΤ
(顼֤ꡢ
.I errno

.B EIDRM
ꤵ)
ƤӽФץŬڤøäƤ뤫
ƤӽФץμ¸桼 ID å塼κԤ
ͭԤμ¸桼 ID ǤʤФʤʤ
.TP
.BR IPC_INFO " (Linux ͭ)"
ƥΤǤΥå塼¤ȥѥ᡼˴ؤ
.I buf
ؤ¤Τ֤
ι¤Τ
.I msginfo
Ǥ (Τᥭ㥹ȤɬפǤ)
.I msginfo

.B _GNU_SOURCE
ǽޥ줿
.I <sys/msg.h>
ǰʲΤ褦:
.nf
.in +4n

struct msginfo {
    int msgpool; /* åǡݻ˻Ѥ
                    Хåեס礭 (1024 Хñ);
                    ͥǤ̤ */
    int msgmap;  /* åޥåפκ票ȥ;
                    ͥǤ̤ */
    int msgmax;  /* ĤΥå˽񤭹߲ǽ
                    Хȿ */
    int msgmnb;  /* ĤΥ塼˽񤭹߲ǽʺХȿ;
                    (msgget(2) Ǥ) 塼 msg_qbytes
                    ν˻Ѥ */
    int msgmni;  /* å塼οκ */
    int msgssz;  /* åȤΥ;
                    ͥǤ̤ */
    int msgtql;  /* ƥ塼κå;
                    ͥǤ̤ */
    unsigned short int msgseg;
                 /* 祻ȿ; ͥǤ̤ */
};

.in
.fi

.I msgmni ,
.I msgmax ,
.I msgmnb

.I /proc
ˤƱ̾ΥեͳѹǽǤ롣
ܤ
.BR proc (5)
򻲾ȡ
.TP
.BR MSG_INFO " (Linux ͭ)"
.B IPC_INFO
ΤȤƱǼ
.I msginfo
¤Τ֤
âʲΥեɤˤϥå塼
񤷤Ƥ륷ƥ񸻤˴ؤ󤬳Ǽۤʤ롣
.I msgpool
եɤϸߥƥ¸ߤå塼ο֤
.I msgmap
եɤϥƥƤΥ塼äƤå֤
.I msgtql
եɤϥƥƤΥ塼äƤå
Хȿ֤
.TP
.BR MSG_STAT " (Linux ͭ)"
.B IPC_STAT
Ʊ
.I msqid_ds
¤Τ֤
â
.I msqid
ϡ塼̻ҤǤϤʤƥƤΥå塼
˴ؤ륫ͥؤΥǥåǤ롣
.SH ֤
ȡ
.BR IPC_STAT ,
.BR IPC_SET ,
.B IPC_RMID
 0 ֤
.B IPC_INFO

.B MSG_INFO
ϡȡƤΥå塼˴ؤ
Ƥ륫ͥλ楨ȥΥǥå
֤ͤ
(ξϡƥƤΥå塼˴ؤ
뤿ˡ
.B MSG_STAT
򷫤֤¹Ԥݤ˻ѤǤ)
.B MSG_STAT
ϡȡ
.I msqid
ǻꤵ줿ǥåĥå塼μ̻Ҥ֤

顼ξ \-1 ֤
.I errno
Ŭڤꤹ롣
.SH 顼
Ԥ硢
.I errno
ϰʲͤΤɤ줫Ĥꤵ:
.TP
.B EACCES

.I cmd

.B IPC_STAT
ޤ
.B MSG_STAT
ƤӽФץå塼
.I msqid
Фɤ߹ߵĤäƤ餺
.B CAP_IPC_OWNER
ѥӥƥäƤʤ
.TP
.B EFAULT

.I cmd

.B IPC_SET

.B IPC_STAT
ǡݥ
.I buf
ǻؤƤ륢ɥ쥹ǽǤʤ
.TP
.B EIDRM
å塼줿
.TP
.B EINVAL
.I cmd
ޤ
.I msqid
ͤꤵ줿
⤷ϡ
.B MSG_STAT
ξˡ
.I msqid
ǻꤵ줿ǥå̤ͤѤΥåȤ򻲾ȤƤ
.TP
.B EPERM

.I cmd

.B IPC_SET

.B IPC_RMID
Ǥ뤬ƤӽФץμ¸桼 ID å塼
.RI ( msg_perm.cuid
ȤƸĤ) 

.RI ( msg_perm.uid
ȤƸĤ) ͭԤΤǤʤ
ĸƤӽФץø (Linux Ǥ
.B CAP_SYS_ADMIN
ѥӥƥ) ʤ
.SH 
SVr4, POSIX.1-2001.
.\" SVID ˤ EIDRM 顼ˤĤƤεҤϤʤ
.SH 
.BR IPC_INFO ,
.BR MSG_STAT ,
.B MSG_INFO
ϡ
.BR ipcs (8)
ץdzƺѤλ񸻤˴ؤ󶡤뤿
ѤƤ롣衢ѹ줿ꡢ
/proc ե륷ƥΥ󥿥ե˰ư뤫⤷ʤ


\fIstruct msqid_ds\fP ¿Υեɤϡ
Linux 2.2 Ǥ
.I short
äLinux 2.4 Ǥ
.I long
ˤʤä
ˤϡglibc-2.1.91 ʹߤδĶ
ƥѥ뤹нʬǤ롣
(ͥϿθƤӽФȸŤθƤӽФ
.I cmd

.B IPC_64
ե饰Ƕ̤롣)
.SH Ϣ
.BR msgget (2),
.BR msgrcv (2),
.BR msgsnd (2),
.BR capabilities (7),
.BR mq_overview (7),
.BR svipc (7)