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Diffstat (limited to 'lib/libc/sys/semctl.2')
| -rw-r--r-- | lib/libc/sys/semctl.2 | 200 |
1 files changed, 0 insertions, 200 deletions
diff --git a/lib/libc/sys/semctl.2 b/lib/libc/sys/semctl.2 deleted file mode 100644 index 85657589eca6..000000000000 --- a/lib/libc/sys/semctl.2 +++ /dev/null @@ -1,200 +0,0 @@ -.\" -.\" Copyright (c) 1995 David Hovemeyer <daveho@infocom.com> -.\" -.\" All rights reserved. -.\" -.\" Redistribution and use in source and binary forms, with or without -.\" modification, are permitted provided that the following conditions -.\" are met: -.\" 1. Redistributions of source code must retain the above copyright -.\" notice, this list of conditions and the following disclaimer. -.\" 2. Redistributions in binary form must reproduce the above copyright -.\" notice, this list of conditions and the following disclaimer in the -.\" documentation and/or other materials provided with the distribution. -.\" -.\" THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY EXPRESS OR -.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES -.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. -.\" IN NO EVENT SHALL THE DEVELOPERS BE LIABLE FOR ANY DIRECT, INDIRECT, -.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT -.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, -.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY -.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT -.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF -.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. -.\" -.Dd July 9, 2020 -.Dt SEMCTL 2 -.Os -.Sh NAME -.Nm semctl -.Nd control operations on a semaphore set -.Sh LIBRARY -.Lb libc -.Sh SYNOPSIS -.In sys/types.h -.In sys/ipc.h -.In sys/sem.h -.Ft int -.Fn semctl "int semid" "int semnum" "int cmd" ... -.Sh DESCRIPTION -The -.Fn semctl -system call -performs the operation indicated by -.Fa cmd -on the semaphore set indicated by -.Fa semid . -A fourth argument, a -.Fa "union semun arg" , -is required for certain values of -.Fa cmd . -For the commands that use the -.Fa arg -argument, -.Fa "union semun" -must be defined as follows: -.Bd -literal -union semun { - int val; /* value for SETVAL */ - struct semid_ds *buf; /* buffer for IPC_STAT & IPC_SET */ - u_short *array; /* array for GETALL & SETALL */ -}; -.Ed -Non-portable software may define -.Dv _WANT_SEMUN -before including -.Pa sys/sem.h -to use the system definition of -.Fa "union semun" . -.Pp -Commands are performed as follows: -.\" -.\" This section based on Stevens, _Advanced Programming in the UNIX -.\" Environment_. -.\" -.Bl -tag -width IPC_RMIDXXX -.It Dv IPC_STAT -Fetch the semaphore set's -.Fa "struct semid_ds" , -storing it in the memory pointed to by -.Fa arg.buf . -.It Dv IPC_SET -Changes the -.Fa sem_perm.uid , -.Fa sem_perm.gid , -and -.Fa sem_perm.mode -members of the semaphore set's -.Fa "struct semid_ds" -to match those of the struct pointed to by -.Fa arg.buf . -The calling process's effective uid must -match either -.Fa sem_perm.uid -or -.Fa sem_perm.cuid , -or it must have superuser privileges. -.It IPC_RMID -Immediately removes the semaphore set from the system. -The calling -process's effective uid must equal the semaphore set's -.Fa sem_perm.uid -or -.Fa sem_perm.cuid , -or the process must have superuser privileges. -.It Dv GETVAL -Return the value of semaphore number -.Fa semnum . -.It Dv SETVAL -Set the value of semaphore number -.Fa semnum -to -.Fa arg.val . -Outstanding adjust on exit values for this semaphore in any process -are cleared. -.It Dv GETPID -Return the pid of the last process to perform an operation on -semaphore number -.Fa semnum . -.It Dv GETNCNT -Return the number of processes waiting for semaphore number -.Fa semnum Ns 's -value to become greater than its current value. -.It Dv GETZCNT -Return the number of processes waiting for semaphore number -.Fa semnum Ns 's -value to become 0. -.It Dv GETALL -Fetch the value of all of the semaphores in the set into the -array pointed to by -.Fa arg.array . -.It Dv SETALL -Set the values of all of the semaphores in the set to the values -in the array pointed to by -.Fa arg.array . -Outstanding adjust on exit values for all semaphores in this set, -in any process are cleared. -.El -.Pp -The -.Vt "struct semid_ds" -is defined as follows: -.\" -.\" Taken straight from <sys/sem.h>. -.\" -.Bd -literal -struct semid_ds { - struct ipc_perm sem_perm; /* operation permission struct */ - u_short sem_nsems; /* number of sems in set */ - time_t sem_otime; /* last operation time */ - time_t sem_ctime; /* last change time */ - /* Times measured in secs since */ - /* 00:00:00 GMT, Jan. 1, 1970 */ -}; -.Ed -.Sh RETURN VALUES -On success, when -.Fa cmd -is one of -.Dv GETVAL , GETPID , GETNCNT -or -.Dv GETZCNT , -.Fn semctl -returns the corresponding value; otherwise, 0 is returned. -On failure, -1 is returned, and -.Va errno -is set to indicate the error. -.Sh ERRORS -The -.Fn semctl -system call -will fail if: -.Bl -tag -width Er -.It Bq Er EINVAL -No semaphore set corresponds to -.Fa semid . -.It Bq Er EINVAL -The -.Fa semnum -argument -is not in the range of valid semaphores for given semaphore set. -.It Bq Er EPERM -The calling process's effective uid does not match the uid of -the semaphore set's owner or creator. -.It Bq Er EACCES -Permission denied due to mismatch between operation and mode of -semaphore set. -.It Bq Er ERANGE -.Dv SETVAL -or -.Dv SETALL -attempted to set a semaphore outside the allowable range -.Bq 0 .. Dv SEMVMX . -.El -.Sh SEE ALSO -.Xr semget 2 , -.Xr semop 2 -.Sh BUGS -.Dv SETALL -may update some semaphore elements before returning an error. |