.\" 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.\" manual page may be incorrect or out-of-date.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 17:53:56 1996 by Eric S. Raymond <esr@thyrsus.com>
.\" Modified Fri Jun 19 10:59:15 1998 by Andries Brouwer <aeb@cwi.nl>
.\" Modified Sun Feb 18 01:59:29 2001 by Andries Brouwer <aeb@cwi.nl>
.\" Modified 20 Dec 2001, Michael Kerrisk <mtk.manpages@gmail.com>
.\" Modified 21 Dec 2001, aeb
.\" 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
.\"	Rewrote semun text
.\"	Added semid_ds and ipc_perm structure definitions
.\" 2005-08-02, mtk: Added IPC_INFO, SEM_INFO, SEM_STAT descriptions.
.\"
.\" Japanese Version Copyright (c) 1997,1998 HANATAKA Shinya
.\"         all rights reserved.
.\" Translated 1997-02-23, HANATAKA Shinya <hanataka@abyss.rim.or.jp>
.\" Modified 1998-09-10, HANATAKA Shinya <hanataka@abyss.rim.or.jp>
.\" Updated & Modified 2001-06-03, Yuichi SATO <ysato@h4.dion.ne.jp>
.\" Updated & Modified 2002-01-02, Yuichi SATO
.\" Updated & Modified 2005-01-03, Yuichi SATO <ysato444@yahoo.co.jp>
.\" Updated & Modified 2005-10-10, Akihiro MOTOKI <amotoki@dd.iij4u.or.jp>
.\"
.\"WORD:	semaphore		ޥե
.\"WORD:	semaphore set		ޥե
.\"WORD:	union			
.\"WORD:	buffer			Хåե
.\"WORD:	member			С
.\"WORD:	superuser		ѡ桼
.\"WORD:	effective uid		¸桼 ID
.\"WORD:	creator			
.\"WORD:	owner			ͭ
.\"WORD:	entry			ȥ
.\"WORD:	undo			ɥ
.\"WORD:	implement		
.\"WORD:	feature test macro	ǽޥ
.\"
.TH SEMCTL 2 2004-11-10 "Linux" "Linux Programmer's Manual"
.SH ̾
semctl \- ޥեԤʤ
.SH 
.nf
.B #include <sys/types.h>
.B #include <sys/ipc.h>
.B #include <sys/sem.h>
.sp
.BI "int semctl(int " semid ", int " semnum ", int " cmd ", ...);"
.fi
.SH 
.BR semctl ()
ϡ
.I semid
ǻꤵ줿ޥե (semaphore set)
ޤϥޥե
.I semnun
ܤΥޥեФơ
.I cmd
ǻꤵ줿Ԥʤ
(Υޥեֹ 0 Ϥޤ)
.PP
δؿϡ
.I cmd
ͤ˰¸ơ3 Ĥޤ 4 Ĥΰġ
 4 Ĥξ硢 4 η
.I "union semun"
Ǥ롣
\fIƤӽФץ\fPϡ
ζ (union) ʲΤ褦ʤФʤʤ

.nf
.in +4n
union semun {
    int              val;    /* SETVAL  */
    struct semid_ds *buf;    /* IPC_STAT, IPC_SET ѤΥХåե */
    unsigned short  *array;  /* GETALL, SETALL Ѥ */
    struct seminfo  *__buf;  /* IPC_INFO ѤΥХåե
                                (Linux ͭ) */
};
.in
.fi
.PP
.I semid_ds
ǡ¤Τ \fI<sys/sem.h>\fP ǰʲΤ褦Ƥ:
.nf
.in +4n

struct semid_ds {
    struct ipc_perm sem_perm;  /* ͭȵ */
    time_t          sem_otime; /* Ǹ semop λ */
    time_t          sem_ctime; /* ǸѹԤ줿 */
    unsigned short  sem_nsems; /* Υޥեο */
};
.fi
.PP
.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;            /* semget(2) Ϳ륭 */
    uid_t \fBuid\fP;            /* ͭ (owner) μ¸ UID */
    gid_t \fBgid\fP;            /* ͭԤμ¸ GID */
    uid_t cuid;           /*  (creator) μ¸ UID */
    gid_t cgid;           /* Ԥμ¸ GID */
    unsigned short \fBmode\fP;  /*  */
    unsigned short seq;   /* ֹ */
};
.in
.fi
.PP
.I cmd
Ȥͭͤ
.TP 12
.B IPC_STAT
.I semid
˴ϢŤ줿ͥǡ¤Τξ
.I arg.buf
ǻؤ줿
.I semid_ds
¤Τإԡ롣
.I semnum
̵뤵롣
ƤӽФץϤΥޥեФ
ɤ߹ߵĤʤФʤʤ
.TP
.B IPC_SET
.I arg.buf
ǻꤵ줿
.I semid_ds
¤ΤΥСΤĤͤ
Υޥե˴ϢŤ줿ͥǡ¤Τ˽񤭹ߡ
.I sem_ctime
Сͤ⹹롣
¤ΤΰʲΥС:
.IR sem_perm.uid ,
.IR sem_perm.gid ,
.I sem_perm.mode
(κDz 9 ӥå)
ƤӽФץμ¸ UID ͭ
.RI ( sem_perm.uid )
ޤϺ
.RI ( sem_perm.cuid )
Ȱפ뤫ƤӽФͤøʤФʤʤ
.I semnum
̵뤵롣
.TP
.B IPC_RMID
ޥե򤿤˺ν
.BR semop (2)
ǥ֥åƤƤΥץܳФᤵ
(顼֤ͤơ
.I errno

.B EIDRM
ꤵ)
ƤӽФץμ¸桼 ID 
ΥޥեκԤޤϽͭԤȰפ뤫
ƤӽФͤøʤФʤʤ
.I semnum
̵뤵롣
.TP
.BR IPC_INFO " (Linux ͭ)"
ƥΤǤΥޥե¤ȥѥ᡼˴ؤ
.I arg.__buf
ؤ¤Τ֤
ι¤Τ
.I seminfo
Ǥ롣
.I seminfo

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

struct  seminfo {
    int semmap;  /* ޥեޥåפκ票ȥ;
                    ̤ */
    int semmni;  /* ޥեκ */
    int semmns;  /* ޥեΥޥե
                     */
    int semmnu;  /* ɥ¤ΤΥƥΤǤ
                    ; ̤ */
    int semmsl;  /* ĤΥޥեκ祻ޥե */
    int semopm;  /* semop(2) Ϥκ */
    int semume;  /* ץΥɥȥ
                    κ; ̤ */
    int semusz;  /* ¤ sem_undo Υ */
    int semvmx;  /* ޥեκ */
    int semaem;  /* ޥեĴ (semaphore adjustment;
                     SEM_UNDO) Τ˵Ͽ */
};

.in
.fi

.IR semmsl ,
.IR semmns ,
.IR semopm ,
.I semmni

.I /proc/sys/kernel/sem
ͳѹǽǤ롣
ܤ
.BR proc (5)
򻲾ȡ
.TP
.BR SEM_INFO " (Linux ͭ)"
.B IPC_INFO
ΤȤƱǼ
.I seminfo
¤Τ֤
âʲΥեɤˤϥޥե񤷤Ƥ륷ƥ񸻤
ؤ󤬳Ǽۤʤ롣
.I semusz
եɤϸߥƥ¸ߤ륻ޥեο֤
.I semaem
եɤϥƥƤΥޥե˴ޤޤ
ޥե֤
.TP
.BR SEM_STAT " (Linux ͭ)"
.B IPC_STAT
Ʊ
.I semid_ds
¤Τ֤
â
.I semid
ϡޥե̻ҤǤϤʤƥƤΥޥե
˴ؤ륫ͥؤΥǥåǤ롣
.TP
.B GETALL
ƤΥޥե
.B semval
 (ߤ) 
.I arg.array
֤
.I semnum
̵뤵롣
ƤӽФץϤΥޥեɤ߹ߵĤʤФʤʤ
.TP
.B GETNCNT
ƥॳϽ
.I semnum
ܤΥޥե
.B semncnt
 (ΥޥեͤäΤԤäƤץ) ֤
(
.I semnum
ܤΥޥե
.B semval
äԤäƤץο֤)
ƤӽФץϤΥޥեɤ߹ߵĤʤФʤʤ
.TP
.B GETPID
ƥॳϽ
.I semnum
ܤΥޥե
.B sempid
 (
.I semnum
ܤΥޥե˺Ǹ
.BR semop (2)
¹Ԥץ PID) ֤
ƤӽФץϤΥޥեɤ߹ߵĤʤФʤʤ
.TP
.B GETVAL
ƥॳϽ
.I semnum
ܤΥޥե
.B semval
֤ͤ
ƤӽФץϤΥޥեɤ߹ߵĤʤФʤʤ
.TP
.B GETZCNT
ƥॳϽ
.I semnum
ܤΥޥե
.B semzcnt
 (Υޥեͤ 0 ˤʤΤԤäƤץο) ֤
(
.I semnum
ܤΥޥե
.B semval
ͤ 0 ˤʤΤԤäƤץο֤)
ƤӽФץϤΥޥեɤ߹ߵĤʤФʤʤ
.TP
.B SETALL
ƤΥޥե
.B semval

.I arg.array
ǻꤵ줿ͤꤹ롣
ν˴Ϣ
.I semid_ds
¤Τ
.I sem_ctime
Сͤ⹹롣
ƤΥץΥޥեѹˤĤƤΥɥȥ
.RB ( semop (2)
򻲾) Ͼõ (clear) 롣
ޥեͤѹˤꡢ¾Υץǥ֥åƤ
.BR semop (2)
³ԤĤȡΥץϵ (wake up)
.I semnum
̵뤵롣
ƤӽФץϤΥޥե
ѹ (񤭹) ĤʤФʤʤ
.TP
.B SETVAL

.I semnum
ܤΥޥե
.B semval

.I arg.val
ͤꤹ롣ν˴Ϣ
.I semid_ds
¤Τ
.I sem_ctime
Сͤ⹹롣
ƤΥץΥޥեѹˤĤƤΥɥȥϾõ롣
ޥեͤѹˤꡢ¾Υץǥ֥åƤ
.BR semop (2)
³ԤĤȡΥץϵ (wake up)
ƤӽФץϤΥޥե
ѹ (񤭹) ĤʤФʤʤ
.SH ֤
Ԥ硢
.BR semctl ()
 \-1 ֤
.I errno
ˤΥ顼򼨤

ǤʤХƥॳ
.I cmd
ˤäưʲǤʤ֤ͤ:
.TP 11
.B GETNCNT
.B semncnt

.TP
.B GETPID
.B sempid

.TP
.B GETVAL
.B semval

.TP
.B GETZCNT
.B semzcnt

.TP
.B IPC_INFO
ƤΥޥե˴ؤƤ륫ͥλ
ȥΥǥåκ
(ξϡƥƤΥޥե˴ؤ뤿
.B SEM_STAT
򷫤֤¹Ԥݤ˻ѤǤ)
.TP
.B SEM_INFO
.B IPC_INFO
Ʊ
.TP
.B SEM_STAT
.I semid
ǻꤵ줿ǥåĥޥեμ̻
.LP
.I cmd
ͤʳξ硢 0 ֤롣
.SH 顼
Ԥ
.I errno
ˤϰʲͤΤɤ줫ꤵ:
.TP 11
.B EACCES
.I cmd

.BR GETALL ,
.BR GETPID ,
.BR GETVAL ,
.BR GETNCNT ,
.BR GETZCNT ,
.BR IPC_STAT ,
.BR SEM_STAT ,
.BR SETALL ,
.B SETVAL
Τβ줫ͤ
ƤӽФץޥեФɬפȤĤ
.B CAP_IPC_OWNER
ѥӥƥ (capability) äƤʤ
.TP
.B EFAULT
.I arg.buf
ޤ
.I arg.array
ǻؤƤ륢ɥ쥹˥뤳ȤǤʤ
.TP
.B EIDRM
ޥե礬줿
.TP
.B EINVAL
.I cmd
ޤ
.I semid
̵ͤꤵ줿
⤷ϡ
.B SEM_STAT
ξˡ
.I semid
ǻꤵ줿ǥå̤ͤѤΥåȤ򻲾ȤƤ
.TP
.B EPERM
.I cmd

.B IPC_SET
ޤ
.B IPC_RMID
ꤵ졢ƤӽФץμ¸桼 ID ޥե
.RI ( sem_perm.cuid
ǸĤ) Ԥޤ
.RI ( sem_perm.uid
ǸĤ) ͭԤǤʤ
ץ
.B CAP_SYS_ADMIN
ѥӥƥʤ
.TP
.B ERANGE
.I cmd

.B SETALL
ޤ
.B SETVAL
ꤵ졢(ΥޥեΤɤ줫)
.B semval
ꤵͤ 0 꾮
.B SEMVMX
礭
.SH 
SVr4, POSIX.1-2001.
.\" SVr4 ˤϡ¾ EINVAL, EOVERFLOW 顼ˤĤƤεҤ롣
.SH 
.BR IPC_INFO ,
.BR SEM_STAT ,
.B SEM_INFO

.BR ipcs (8)
ץˤäƳ줿񸻤ˤĤƾ󶡤뤿˻Ѥ롣
ŪˤϤѹ뤫
/proc ե롦ƥࡦ󥿥ե˰ư뤫⤷ʤ
.LP
\fI¤ semid_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
.PP
ΥС glibc Ǥϡ
.I semun
Τ \fI<sys/sem.h>\fP Ƥ
POSIX.1-2001 ǤϸƤӽФ¦ζΤɬפ롣
ζΤ\fIʤ\fP glibc ΥСǤϡ
ޥ
.B _SEM_SEMUN_UNDEFINED
 \fI<sys/sem.h>\fP Ƥ롣
.PP
ʲ
.BR semctl ()
˱ƶ륻ޥեΥƥ:
.TP 11
.B SEMVMX
.B semval
κ : ¸ (32767)
.LP
ܿ뤿ΰɤˡϡ 4 Ĥΰ
.BR semctl ()
ƤӽФȤǤ롣
.SH Ϣ
.BR ipc (2),
.BR semget (2),
.BR semop (2),
.BR capabilities (7),
.BR sem_overview (7),
.BR svipc (7)