Add man pages for the sem_*() functions.
Approved by: jkh
This commit is contained in:
Jason Evans
parent
945111e5a7
commit
b0a1b4f809
83
lib/libc/gen/sem_destroy.3
Normal file
83
lib/libc/gen/sem_destroy.3
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@ -0,0 +1,83 @@
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.\" Copyright (C) 2000 Jason Evans <jasone@canonware.com>.
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.\" All rights reserved.
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.\"
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.\" Redistribution and use in source and binary forms, with or without
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||||||
|
.\" modification, are permitted provided that the following conditions
|
||||||
|
.\" are met:
|
||||||
|
.\" 1. Redistributions of source code must retain the above copyright
|
||||||
|
.\" notice(s), this list of conditions and the following disclaimer as
|
||||||
|
.\" the first lines of this file unmodified other than the possible
|
||||||
|
.\" addition of one or more copyright notices.
|
||||||
|
.\" 2. Redistributions in binary form must reproduce the above copyright
|
||||||
|
.\" notice(s), this list of conditions and the following disclaimer in
|
||||||
|
.\" the documentation and/or other materials provided with the
|
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|
.\" distribution.
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|
.\"
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.\" THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER(S) ``AS IS'' AND ANY
|
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|
.\" EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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||||||
|
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
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|
.\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) BE
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|
.\" LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
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|
.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
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|
.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
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.\" BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
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|
.\" WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
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.\" OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
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.\" EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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.\"
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.\" $FreeBSD$
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.Dd February 15, 2000
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.Dt SEM_DESTROY 3
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.Os
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.Sh NAME
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.Nm sem_destroy
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.Nd destroy an unnamed semaphore
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.Sh SYNOPSIS
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.Fd #include <semaphore.h>
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.Ft int
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.Fn sem_destroy "sem_t *sem"
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.Sh DESCRIPTION
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The
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.Fn sem_destroy
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function destroys the unnamed semaphore pointed to by
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.Fa sem .
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After a successful call to
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.Fn sem_destroy ,
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.Fa sem
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is unuseable until re-initialized by another call to
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.Fn sem_init .
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.Sh RETURN VALUES
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If successful,
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.Fn sem_destroy
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returns 0. Otherwise, -1 is returned and
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.Va errno
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is set to indicate the type of
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error.
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.Sh ERRORS
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.Fn sem_destroy
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will fail if:
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.Bl -tag -width Er
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.It Bq Er EINVAL
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.Fa sem
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points to an invalid semaphore.
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.It Bq Er EBUSY
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There are currently threads blocked on the semaphore that
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.Fa sem
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points to.
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.El
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.Sh SEE ALSO
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.Xr sem_init 3
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.Sh STANDARDS
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.Fn sem_destroy
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conforms to ISO/IEC 9945-1 ANSI/IEEE
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.Pq Dq Tn POSIX
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Std 1003.1 1996 Edition.
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.Pp
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POSIX does not define the behavior of
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.Fn sem_destroy
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if called while there are threads blocked on
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.Fa sem ,
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but this implementation is guaranteed to return -1 and set
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.Va errno
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to EBUSY if there are threads blocked on
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.Fa sem .
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77
lib/libc/gen/sem_getvalue.3
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77
lib/libc/gen/sem_getvalue.3
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@ -0,0 +1,77 @@
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.\" Copyright (C) 2000 Jason Evans <jasone@canonware.com>.
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.\" All rights reserved.
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.\"
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.\" Redistribution and use in source and binary forms, with or without
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|
.\" modification, are permitted provided that the following conditions
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||||||
|
.\" are met:
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|
.\" 1. Redistributions of source code must retain the above copyright
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||||||
|
.\" notice(s), this list of conditions and the following disclaimer as
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|
.\" the first lines of this file unmodified other than the possible
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||||||
|
.\" addition of one or more copyright notices.
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||||||
|
.\" 2. Redistributions in binary form must reproduce the above copyright
|
||||||
|
.\" notice(s), this list of conditions and the following disclaimer in
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|
.\" the documentation and/or other materials provided with the
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|
.\" distribution.
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|
.\"
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.\" THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER(S) ``AS IS'' AND ANY
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|
.\" EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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|
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
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|
.\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) BE
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.\" LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
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|
.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
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.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
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.\" BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
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.\" WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
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.\" OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
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.\" EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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.\"
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.\" $FreeBSD$
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.Dd February 15, 2000
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.Dt SEM_GETVALUE 3
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.Os
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.Sh NAME
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.Nm sem_getvalue
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.Nd get the value of a semaphore
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.Sh SYNOPSIS
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.Fd #include <semaphore.h>
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.Ft int
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.Fn sem_getvalue "sem_t *sem" "int *sval"
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.Sh DESCRIPTION
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The
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.Fn sem_getvalue
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function sets the variable pointed to by
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.Fa sval
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to the current value of the semaphore pointed to by
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.Fa sem ,
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as of the time that the call to
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.Fn sem_getvalue
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is actually run.
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.Sh RETURN VALUES
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If successful,
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.Fn sem_getvalue
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returns 0. Otherwise, -1 is returned and
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.Va errno
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is set to indicate the type of
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error.
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.Sh ERRORS
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.Fn sem_getvalue
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will fail if:
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.Bl -tag -width Er
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.It Bq Er EINVAL
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.Fa sem
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points to an invalid semaphore.
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.El
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.Sh SEE ALSO
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.Xr sem_post 3 ,
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.Xr sem_wait 3 ,
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.Xr sem_trywait 3
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.Sh STANDARDS
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.Fn sem_getvalue
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conforms to ISO/IEC 9945-1 ANSI/IEEE
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.Pq Dq Tn POSIX
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Std 1003.1 1996 Edition.
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.Pp
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The value of the semaphore is never negative, even if there are threads blocked
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on the semaphore. POSIX is somewhat ambiguous in its wording with regard to
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what the value of the semaphore should be if there are blocked waiting threads,
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but this behavior is conformant, given the wording of the specification.
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100
lib/libc/gen/sem_init.3
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100
lib/libc/gen/sem_init.3
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@ -0,0 +1,100 @@
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.\" Copyright (C) 2000 Jason Evans <jasone@canonware.com>.
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.\" All rights reserved.
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.\"
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.\" Redistribution and use in source and binary forms, with or without
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|
.\" modification, are permitted provided that the following conditions
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||||||
|
.\" are met:
|
||||||
|
.\" 1. Redistributions of source code must retain the above copyright
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||||||
|
.\" notice(s), this list of conditions and the following disclaimer as
|
||||||
|
.\" the first lines of this file unmodified other than the possible
|
||||||
|
.\" addition of one or more copyright notices.
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||||||
|
.\" 2. Redistributions in binary form must reproduce the above copyright
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||||||
|
.\" notice(s), this list of conditions and the following disclaimer in
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|
.\" the documentation and/or other materials provided with the
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|
.\" distribution.
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|
.\"
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.\" THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER(S) ``AS IS'' AND ANY
|
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|
.\" EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
||||||
|
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
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||||||
|
.\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) BE
|
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|
.\" LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
|
||||||
|
.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
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||||||
|
.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
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||||||
|
.\" BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
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||||||
|
.\" WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
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|
.\" OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
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.\" EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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.\"
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.\" $FreeBSD$
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.Dd February 15, 2000
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.Dt SEM_INIT 3
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.Os
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.Sh NAME
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.Nm sem_init
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.Nd initialize an unnamed semaphore
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.Sh SYNOPSIS
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.Fd #include <semaphore.h>
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.Ft int
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.Fn sem_init "sem_t *sem" "int pshared" "unsigned int value"
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.Sh DESCRIPTION
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The
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.Fn sem_init
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function initializes the unnamed semaphore pointed to by
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.Fa sem
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to have the value
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.Fa value .
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A non-zero value for
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.Fa pshared
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specifies a shared semaphore that can be used by multiple processes, which this
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implementation is not capable of.
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.Pp
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Following a successful call to
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.Fn sem_init ,
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.Fa sem
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can be used as an argument in subsequent calls to
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.Fa sem_wait ,
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.Fa sem_trywait ,
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.Fa sem_post ,
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and
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.Fa sem_destroy .
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.Fa sem
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is no longer valid after a successful call to
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.Fa sem_destroy .
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.Sh RETURN VALUES
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If successful,
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.Fn sem_init
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returns 0. Otherwise, -1 is returned and
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.Va errno
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is set to indicate the type of
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error.
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.Sh ERRORS
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.Fn sem_init
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will fail if:
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.Bl -tag -width Er
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.It Bq Er EINVAL
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.Fa value
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exceeds SEM_VALUE_MAX.
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.It Bq Er ENOSPC
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Memory allocation error.
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.It Bq Er EPERM
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Unable to initialize a shared semaphore.
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.El
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.Sh SEE ALSO
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.Xr sem_wait 3 ,
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.Xr sem_trywait 3 ,
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.Xr sem_post 3 ,
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.Xr sem_destroy
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.Sh STANDARDS
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.Fn sem_init
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conforms to ISO/IEC 9945-1 ANSI/IEEE
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.Pq Dq Tn POSIX
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Std 1003.1 1996 Edition.
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.Pp
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This implementation does not support shared semaphores, and reports this fact
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by setting
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.Va errno
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to EPERM. This is perhaps a stretch of the intention of POSIX, but is
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compliant, with the caveat that
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.Fn sem_init
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always reports a permissions error when an attempt to create a shared semaphore
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is made.
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80
lib/libc/gen/sem_open.3
Normal file
80
lib/libc/gen/sem_open.3
Normal file
@ -0,0 +1,80 @@
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.\" Copyright (C) 2000 Jason Evans <jasone@canonware.com>.
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.\" All rights reserved.
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|
.\"
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.\" Redistribution and use in source and binary forms, with or without
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||||||
|
.\" modification, are permitted provided that the following conditions
|
||||||
|
.\" are met:
|
||||||
|
.\" 1. Redistributions of source code must retain the above copyright
|
||||||
|
.\" notice(s), this list of conditions and the following disclaimer as
|
||||||
|
.\" the first lines of this file unmodified other than the possible
|
||||||
|
.\" addition of one or more copyright notices.
|
||||||
|
.\" 2. Redistributions in binary form must reproduce the above copyright
|
||||||
|
.\" notice(s), this list of conditions and the following disclaimer in
|
||||||
|
.\" the documentation and/or other materials provided with the
|
||||||
|
.\" distribution.
|
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|
.\"
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.\" THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER(S) ``AS IS'' AND ANY
|
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|
.\" 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 COPYRIGHT HOLDER(S) 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.
|
||||||
|
.\"
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.\" $FreeBSD$
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.Dd February 15, 2000
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.Dt SEM_OPEN 3
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.Os
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.Sh NAME
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.Nm sem_open ,
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.Nm sem_close ,
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.Nm sem_unlink
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.Nd named semaphore operations
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.Sh SYNOPSIS
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.Fd #include <semaphore.h>
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.Ft sem_t *
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.Fn sem_open "const char *name" "int oflag" "..."
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.Ft int
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.Fn sem_close "sem_t *sem"
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.Ft int
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.Fn sem_unlink "const char *name"
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.Sh DESCRIPTION
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|
The
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.Fn sem_open ,
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.Fn sem_close ,
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and
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.Fn sem_unlink
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functions are not supported by this implementation.
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.Sh RETURN VALUES
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.Fn sem_open
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|
returns SEM_FAILED and sets
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.Va errno
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to indicate an error.
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.Fn sem_close
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and
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.Fn sem_unlink
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return -1 and set
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.Va errno
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|
to indicate an error.
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.Sh ERRORS
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.Fn sem_open ,
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.Fn sem_close ,
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and
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.Fn sem_unlink
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will fail:
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.Bl -tag -width Er
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.It Bq Er ENOSYS
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Function not supported by this implementation.
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.El
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.Sh STANDARDS
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.Fn sem_open ,
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.Fn sem_close ,
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and
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.Fn sem_unlink
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|
conform to ISO/IEC 9945-1 ANSI/IEEE
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.Pq Dq Tn POSIX
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|
Std 1003.1 1996 Edition.
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71
lib/libc/gen/sem_post.3
Normal file
71
lib/libc/gen/sem_post.3
Normal file
@ -0,0 +1,71 @@
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.\" Copyright (C) 2000 Jason Evans <jasone@canonware.com>.
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|
.\" All rights reserved.
|
||||||
|
.\"
|
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|
.\" 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(s), this list of conditions and the following disclaimer as
|
||||||
|
.\" the first lines of this file unmodified other than the possible
|
||||||
|
.\" addition of one or more copyright notices.
|
||||||
|
.\" 2. Redistributions in binary form must reproduce the above copyright
|
||||||
|
.\" notice(s), 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 COPYRIGHT HOLDER(S) ``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 COPYRIGHT HOLDER(S) 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.
|
||||||
|
.\"
|
||||||
|
.\" $FreeBSD$
|
||||||
|
.Dd February 15, 2000
|
||||||
|
.Dt SEM_POST 3
|
||||||
|
.Os
|
||||||
|
.Sh NAME
|
||||||
|
.Nm sem_post
|
||||||
|
.Nd increment (unlock) a semaphore
|
||||||
|
.Sh SYNOPSIS
|
||||||
|
.Fd #include <semaphore.h>
|
||||||
|
.Ft int
|
||||||
|
.Fn sem_post "sem_t *sem"
|
||||||
|
.Sh DESCRIPTION
|
||||||
|
The
|
||||||
|
.Fn sem_post
|
||||||
|
function increments (unlocks) the semaphore pointed to by
|
||||||
|
.Fa sem .
|
||||||
|
If there are threads blocked on the semaphore when
|
||||||
|
.Fn sem_post
|
||||||
|
is called, then the highest priority thread that has been blocked the longest on
|
||||||
|
the semaphore will be allowed to return from
|
||||||
|
.Fn sem_wait .
|
||||||
|
.Sh RETURN VALUES
|
||||||
|
If successful,
|
||||||
|
.Fn sem_post
|
||||||
|
returns 0. Otherwise, -1 is returned and
|
||||||
|
.Va errno
|
||||||
|
is set to indicate the type of
|
||||||
|
error.
|
||||||
|
.Sh ERRORS
|
||||||
|
.Fn sem_post
|
||||||
|
will fail if:
|
||||||
|
.Bl -tag -width Er
|
||||||
|
.It Bq Er EINVAL
|
||||||
|
.Fa sem
|
||||||
|
points to an invalid semaphore.
|
||||||
|
.El
|
||||||
|
.Sh SEE ALSO
|
||||||
|
.Xr sem_wait 3 ,
|
||||||
|
.Xr sem_trywait 3
|
||||||
|
.Sh STANDARDS
|
||||||
|
.Fn sem_post
|
||||||
|
conforms to ISO/IEC 9945-1 ANSI/IEEE
|
||||||
|
.Pq Dq Tn POSIX
|
||||||
|
Std 1003.1 1996 Edition.
|
||||||
92
lib/libc/gen/sem_wait.3
Normal file
92
lib/libc/gen/sem_wait.3
Normal file
@ -0,0 +1,92 @@
|
|||||||
|
.\" Copyright (C) 2000 Jason Evans <jasone@canonware.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(s), this list of conditions and the following disclaimer as
|
||||||
|
.\" the first lines of this file unmodified other than the possible
|
||||||
|
.\" addition of one or more copyright notices.
|
||||||
|
.\" 2. Redistributions in binary form must reproduce the above copyright
|
||||||
|
.\" notice(s), 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 COPYRIGHT HOLDER(S) ``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 COPYRIGHT HOLDER(S) 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.
|
||||||
|
.\"
|
||||||
|
.\" $FreeBSD$
|
||||||
|
.Dd February 15, 2000
|
||||||
|
.Dt SEM_WAIT 3
|
||||||
|
.Os
|
||||||
|
.Sh NAME
|
||||||
|
.Nm sem_wait ,
|
||||||
|
.Nm sem_trywait
|
||||||
|
.Nd decrement (lock) a semaphore
|
||||||
|
.Sh SYNOPSIS
|
||||||
|
.Fd #include <semaphore.h>
|
||||||
|
.Ft int
|
||||||
|
.Fn sem_wait "sem_t *sem"
|
||||||
|
.Ft int
|
||||||
|
.Fn sem_trywait "sem_t *sem"
|
||||||
|
.Sh DESCRIPTION
|
||||||
|
The
|
||||||
|
.Fn sem_wait
|
||||||
|
function decrements (locks) the semaphore pointed to by
|
||||||
|
.Fa sem ,
|
||||||
|
but blocks if the value of
|
||||||
|
.Fa sem
|
||||||
|
is zero, until the value is non-zero and the value can be decremented.
|
||||||
|
.Pp
|
||||||
|
The
|
||||||
|
.Fn sem_trywait
|
||||||
|
function decrements (locks) the semaphore pointed to by
|
||||||
|
.Fa sem
|
||||||
|
only if the value is non-zero. Otherwise, the semaphore is not decremented and
|
||||||
|
an error is returned.
|
||||||
|
.Sh RETURN VALUES
|
||||||
|
If successful,
|
||||||
|
.Fn sem_wait
|
||||||
|
and
|
||||||
|
.Fn sem_trywait
|
||||||
|
return 0. Otherwise, -1 is returned and
|
||||||
|
.Va errno
|
||||||
|
is set to indicate the type of
|
||||||
|
error.
|
||||||
|
.Sh ERRORS
|
||||||
|
.Fn sem_wait
|
||||||
|
and
|
||||||
|
.Fn sem_trywait
|
||||||
|
will fail if:
|
||||||
|
.Bl -tag -width Er
|
||||||
|
.It Bq Er EINVAL
|
||||||
|
.Fa sem
|
||||||
|
points to an invalid semaphore.
|
||||||
|
.El
|
||||||
|
.Pp
|
||||||
|
Additionally,
|
||||||
|
.Fn sem_trywait
|
||||||
|
will fail if:
|
||||||
|
.Bl -tag -width Er
|
||||||
|
.It Bq Er EAGAIN
|
||||||
|
The semaphore value was zero, and thus could not be decremented.
|
||||||
|
.El
|
||||||
|
.Sh SEE ALSO
|
||||||
|
.Xr sem_post 3
|
||||||
|
.Sh STANDARDS
|
||||||
|
.Fn sem_wait
|
||||||
|
and
|
||||||
|
.Fn sem_trywait
|
||||||
|
conform to ISO/IEC 9945-1 ANSI/IEEE
|
||||||
|
.Pq Dq Tn POSIX
|
||||||
|
Std 1003.1 1996 Edition.
|
||||||
@ -4,7 +4,8 @@
|
|||||||
|
|
||||||
.PATH: ${.CURDIR}/man
|
.PATH: ${.CURDIR}/man
|
||||||
|
|
||||||
MAN3+= pthread_cleanup_pop.3 \
|
MAN3+= pthread_cancel.3 \
|
||||||
|
pthread_cleanup_pop.3 \
|
||||||
pthread_cleanup_push.3 \
|
pthread_cleanup_push.3 \
|
||||||
pthread_cond_broadcast.3 \
|
pthread_cond_broadcast.3 \
|
||||||
pthread_cond_destroy.3 \
|
pthread_cond_destroy.3 \
|
||||||
@ -12,7 +13,6 @@ MAN3+= pthread_cleanup_pop.3 \
|
|||||||
pthread_cond_signal.3 \
|
pthread_cond_signal.3 \
|
||||||
pthread_cond_timedwait.3 \
|
pthread_cond_timedwait.3 \
|
||||||
pthread_cond_wait.3 \
|
pthread_cond_wait.3 \
|
||||||
pthread_cancel.3 \
|
|
||||||
pthread_create.3 \
|
pthread_create.3 \
|
||||||
pthread_detach.3 \
|
pthread_detach.3 \
|
||||||
pthread_equal.3 \
|
pthread_equal.3 \
|
||||||
@ -38,7 +38,16 @@ MAN3+= pthread_cleanup_pop.3 \
|
|||||||
pthread_rwlockattr_setpshared.3 \
|
pthread_rwlockattr_setpshared.3 \
|
||||||
pthread_self.3 \
|
pthread_self.3 \
|
||||||
pthread_setspecific.3 \
|
pthread_setspecific.3 \
|
||||||
pthread_testcancel.3
|
pthread_testcancel.3 \
|
||||||
|
sem_destroy.3 \
|
||||||
|
sem_getvalue.3 \
|
||||||
|
sem_init.3 \
|
||||||
|
sem_open.3 \
|
||||||
|
sem_post.3 \
|
||||||
|
sem_wait.3
|
||||||
|
|
||||||
MLINKS+= pthread_cancel.3 pthread_setcancelstate.3 \
|
MLINKS+= pthread_cancel.3 pthread_setcancelstate.3 \
|
||||||
pthread_cancel.3 pthread_getcancelstate.3
|
pthread_cancel.3 pthread_getcancelstate.3 \
|
||||||
|
sem_open.3 sem_close.3 \
|
||||||
|
sem_open.3 sem_unlink.3 \
|
||||||
|
sem_wait.3 sem_trywait.3
|
||||||
|
|||||||
83
lib/libc_r/man/sem_destroy.3
Normal file
83
lib/libc_r/man/sem_destroy.3
Normal file
@ -0,0 +1,83 @@
|
|||||||
|
.\" Copyright (C) 2000 Jason Evans <jasone@canonware.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(s), this list of conditions and the following disclaimer as
|
||||||
|
.\" the first lines of this file unmodified other than the possible
|
||||||
|
.\" addition of one or more copyright notices.
|
||||||
|
.\" 2. Redistributions in binary form must reproduce the above copyright
|
||||||
|
.\" notice(s), 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 COPYRIGHT HOLDER(S) ``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 COPYRIGHT HOLDER(S) 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.
|
||||||
|
.\"
|
||||||
|
.\" $FreeBSD$
|
||||||
|
.Dd February 15, 2000
|
||||||
|
.Dt SEM_DESTROY 3
|
||||||
|
.Os
|
||||||
|
.Sh NAME
|
||||||
|
.Nm sem_destroy
|
||||||
|
.Nd destroy an unnamed semaphore
|
||||||
|
.Sh SYNOPSIS
|
||||||
|
.Fd #include <semaphore.h>
|
||||||
|
.Ft int
|
||||||
|
.Fn sem_destroy "sem_t *sem"
|
||||||
|
.Sh DESCRIPTION
|
||||||
|
The
|
||||||
|
.Fn sem_destroy
|
||||||
|
function destroys the unnamed semaphore pointed to by
|
||||||
|
.Fa sem .
|
||||||
|
After a successful call to
|
||||||
|
.Fn sem_destroy ,
|
||||||
|
.Fa sem
|
||||||
|
is unuseable until re-initialized by another call to
|
||||||
|
.Fn sem_init .
|
||||||
|
.Sh RETURN VALUES
|
||||||
|
If successful,
|
||||||
|
.Fn sem_destroy
|
||||||
|
returns 0. Otherwise, -1 is returned and
|
||||||
|
.Va errno
|
||||||
|
is set to indicate the type of
|
||||||
|
error.
|
||||||
|
.Sh ERRORS
|
||||||
|
.Fn sem_destroy
|
||||||
|
will fail if:
|
||||||
|
.Bl -tag -width Er
|
||||||
|
.It Bq Er EINVAL
|
||||||
|
.Fa sem
|
||||||
|
points to an invalid semaphore.
|
||||||
|
.It Bq Er EBUSY
|
||||||
|
There are currently threads blocked on the semaphore that
|
||||||
|
.Fa sem
|
||||||
|
points to.
|
||||||
|
.El
|
||||||
|
.Sh SEE ALSO
|
||||||
|
.Xr sem_init 3
|
||||||
|
.Sh STANDARDS
|
||||||
|
.Fn sem_destroy
|
||||||
|
conforms to ISO/IEC 9945-1 ANSI/IEEE
|
||||||
|
.Pq Dq Tn POSIX
|
||||||
|
Std 1003.1 1996 Edition.
|
||||||
|
.Pp
|
||||||
|
POSIX does not define the behavior of
|
||||||
|
.Fn sem_destroy
|
||||||
|
if called while there are threads blocked on
|
||||||
|
.Fa sem ,
|
||||||
|
but this implementation is guaranteed to return -1 and set
|
||||||
|
.Va errno
|
||||||
|
to EBUSY if there are threads blocked on
|
||||||
|
.Fa sem .
|
||||||
77
lib/libc_r/man/sem_getvalue.3
Normal file
77
lib/libc_r/man/sem_getvalue.3
Normal file
@ -0,0 +1,77 @@
|
|||||||
|
.\" Copyright (C) 2000 Jason Evans <jasone@canonware.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(s), this list of conditions and the following disclaimer as
|
||||||
|
.\" the first lines of this file unmodified other than the possible
|
||||||
|
.\" addition of one or more copyright notices.
|
||||||
|
.\" 2. Redistributions in binary form must reproduce the above copyright
|
||||||
|
.\" notice(s), 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 COPYRIGHT HOLDER(S) ``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 COPYRIGHT HOLDER(S) 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.
|
||||||
|
.\"
|
||||||
|
.\" $FreeBSD$
|
||||||
|
.Dd February 15, 2000
|
||||||
|
.Dt SEM_GETVALUE 3
|
||||||
|
.Os
|
||||||
|
.Sh NAME
|
||||||
|
.Nm sem_getvalue
|
||||||
|
.Nd get the value of a semaphore
|
||||||
|
.Sh SYNOPSIS
|
||||||
|
.Fd #include <semaphore.h>
|
||||||
|
.Ft int
|
||||||
|
.Fn sem_getvalue "sem_t *sem" "int *sval"
|
||||||
|
.Sh DESCRIPTION
|
||||||
|
The
|
||||||
|
.Fn sem_getvalue
|
||||||
|
function sets the variable pointed to by
|
||||||
|
.Fa sval
|
||||||
|
to the current value of the semaphore pointed to by
|
||||||
|
.Fa sem ,
|
||||||
|
as of the time that the call to
|
||||||
|
.Fn sem_getvalue
|
||||||
|
is actually run.
|
||||||
|
.Sh RETURN VALUES
|
||||||
|
If successful,
|
||||||
|
.Fn sem_getvalue
|
||||||
|
returns 0. Otherwise, -1 is returned and
|
||||||
|
.Va errno
|
||||||
|
is set to indicate the type of
|
||||||
|
error.
|
||||||
|
.Sh ERRORS
|
||||||
|
.Fn sem_getvalue
|
||||||
|
will fail if:
|
||||||
|
.Bl -tag -width Er
|
||||||
|
.It Bq Er EINVAL
|
||||||
|
.Fa sem
|
||||||
|
points to an invalid semaphore.
|
||||||
|
.El
|
||||||
|
.Sh SEE ALSO
|
||||||
|
.Xr sem_post 3 ,
|
||||||
|
.Xr sem_wait 3 ,
|
||||||
|
.Xr sem_trywait 3
|
||||||
|
.Sh STANDARDS
|
||||||
|
.Fn sem_getvalue
|
||||||
|
conforms to ISO/IEC 9945-1 ANSI/IEEE
|
||||||
|
.Pq Dq Tn POSIX
|
||||||
|
Std 1003.1 1996 Edition.
|
||||||
|
.Pp
|
||||||
|
The value of the semaphore is never negative, even if there are threads blocked
|
||||||
|
on the semaphore. POSIX is somewhat ambiguous in its wording with regard to
|
||||||
|
what the value of the semaphore should be if there are blocked waiting threads,
|
||||||
|
but this behavior is conformant, given the wording of the specification.
|
||||||
100
lib/libc_r/man/sem_init.3
Normal file
100
lib/libc_r/man/sem_init.3
Normal file
@ -0,0 +1,100 @@
|
|||||||
|
.\" Copyright (C) 2000 Jason Evans <jasone@canonware.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(s), this list of conditions and the following disclaimer as
|
||||||
|
.\" the first lines of this file unmodified other than the possible
|
||||||
|
.\" addition of one or more copyright notices.
|
||||||
|
.\" 2. Redistributions in binary form must reproduce the above copyright
|
||||||
|
.\" notice(s), 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 COPYRIGHT HOLDER(S) ``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 COPYRIGHT HOLDER(S) 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.
|
||||||
|
.\"
|
||||||
|
.\" $FreeBSD$
|
||||||
|
.Dd February 15, 2000
|
||||||
|
.Dt SEM_INIT 3
|
||||||
|
.Os
|
||||||
|
.Sh NAME
|
||||||
|
.Nm sem_init
|
||||||
|
.Nd initialize an unnamed semaphore
|
||||||
|
.Sh SYNOPSIS
|
||||||
|
.Fd #include <semaphore.h>
|
||||||
|
.Ft int
|
||||||
|
.Fn sem_init "sem_t *sem" "int pshared" "unsigned int value"
|
||||||
|
.Sh DESCRIPTION
|
||||||
|
The
|
||||||
|
.Fn sem_init
|
||||||
|
function initializes the unnamed semaphore pointed to by
|
||||||
|
.Fa sem
|
||||||
|
to have the value
|
||||||
|
.Fa value .
|
||||||
|
A non-zero value for
|
||||||
|
.Fa pshared
|
||||||
|
specifies a shared semaphore that can be used by multiple processes, which this
|
||||||
|
implementation is not capable of.
|
||||||
|
.Pp
|
||||||
|
Following a successful call to
|
||||||
|
.Fn sem_init ,
|
||||||
|
.Fa sem
|
||||||
|
can be used as an argument in subsequent calls to
|
||||||
|
.Fa sem_wait ,
|
||||||
|
.Fa sem_trywait ,
|
||||||
|
.Fa sem_post ,
|
||||||
|
and
|
||||||
|
.Fa sem_destroy .
|
||||||
|
.Fa sem
|
||||||
|
is no longer valid after a successful call to
|
||||||
|
.Fa sem_destroy .
|
||||||
|
.Sh RETURN VALUES
|
||||||
|
If successful,
|
||||||
|
.Fn sem_init
|
||||||
|
returns 0. Otherwise, -1 is returned and
|
||||||
|
.Va errno
|
||||||
|
is set to indicate the type of
|
||||||
|
error.
|
||||||
|
.Sh ERRORS
|
||||||
|
.Fn sem_init
|
||||||
|
will fail if:
|
||||||
|
.Bl -tag -width Er
|
||||||
|
.It Bq Er EINVAL
|
||||||
|
.Fa value
|
||||||
|
exceeds SEM_VALUE_MAX.
|
||||||
|
.It Bq Er ENOSPC
|
||||||
|
Memory allocation error.
|
||||||
|
.It Bq Er EPERM
|
||||||
|
Unable to initialize a shared semaphore.
|
||||||
|
.El
|
||||||
|
.Sh SEE ALSO
|
||||||
|
.Xr sem_wait 3 ,
|
||||||
|
.Xr sem_trywait 3 ,
|
||||||
|
.Xr sem_post 3 ,
|
||||||
|
.Xr sem_destroy
|
||||||
|
.Sh STANDARDS
|
||||||
|
.Fn sem_init
|
||||||
|
conforms to ISO/IEC 9945-1 ANSI/IEEE
|
||||||
|
.Pq Dq Tn POSIX
|
||||||
|
Std 1003.1 1996 Edition.
|
||||||
|
.Pp
|
||||||
|
This implementation does not support shared semaphores, and reports this fact
|
||||||
|
by setting
|
||||||
|
.Va errno
|
||||||
|
to EPERM. This is perhaps a stretch of the intention of POSIX, but is
|
||||||
|
compliant, with the caveat that
|
||||||
|
.Fn sem_init
|
||||||
|
always reports a permissions error when an attempt to create a shared semaphore
|
||||||
|
is made.
|
||||||
80
lib/libc_r/man/sem_open.3
Normal file
80
lib/libc_r/man/sem_open.3
Normal file
@ -0,0 +1,80 @@
|
|||||||
|
.\" Copyright (C) 2000 Jason Evans <jasone@canonware.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(s), this list of conditions and the following disclaimer as
|
||||||
|
.\" the first lines of this file unmodified other than the possible
|
||||||
|
.\" addition of one or more copyright notices.
|
||||||
|
.\" 2. Redistributions in binary form must reproduce the above copyright
|
||||||
|
.\" notice(s), 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 COPYRIGHT HOLDER(S) ``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 COPYRIGHT HOLDER(S) 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.
|
||||||
|
.\"
|
||||||
|
.\" $FreeBSD$
|
||||||
|
.Dd February 15, 2000
|
||||||
|
.Dt SEM_OPEN 3
|
||||||
|
.Os
|
||||||
|
.Sh NAME
|
||||||
|
.Nm sem_open ,
|
||||||
|
.Nm sem_close ,
|
||||||
|
.Nm sem_unlink
|
||||||
|
.Nd named semaphore operations
|
||||||
|
.Sh SYNOPSIS
|
||||||
|
.Fd #include <semaphore.h>
|
||||||
|
.Ft sem_t *
|
||||||
|
.Fn sem_open "const char *name" "int oflag" "..."
|
||||||
|
.Ft int
|
||||||
|
.Fn sem_close "sem_t *sem"
|
||||||
|
.Ft int
|
||||||
|
.Fn sem_unlink "const char *name"
|
||||||
|
.Sh DESCRIPTION
|
||||||
|
The
|
||||||
|
.Fn sem_open ,
|
||||||
|
.Fn sem_close ,
|
||||||
|
and
|
||||||
|
.Fn sem_unlink
|
||||||
|
functions are not supported by this implementation.
|
||||||
|
.Sh RETURN VALUES
|
||||||
|
.Fn sem_open
|
||||||
|
returns SEM_FAILED and sets
|
||||||
|
.Va errno
|
||||||
|
to indicate an error.
|
||||||
|
.Fn sem_close
|
||||||
|
and
|
||||||
|
.Fn sem_unlink
|
||||||
|
return -1 and set
|
||||||
|
.Va errno
|
||||||
|
to indicate an error.
|
||||||
|
.Sh ERRORS
|
||||||
|
.Fn sem_open ,
|
||||||
|
.Fn sem_close ,
|
||||||
|
and
|
||||||
|
.Fn sem_unlink
|
||||||
|
will fail:
|
||||||
|
.Bl -tag -width Er
|
||||||
|
.It Bq Er ENOSYS
|
||||||
|
Function not supported by this implementation.
|
||||||
|
.El
|
||||||
|
.Sh STANDARDS
|
||||||
|
.Fn sem_open ,
|
||||||
|
.Fn sem_close ,
|
||||||
|
and
|
||||||
|
.Fn sem_unlink
|
||||||
|
conform to ISO/IEC 9945-1 ANSI/IEEE
|
||||||
|
.Pq Dq Tn POSIX
|
||||||
|
Std 1003.1 1996 Edition.
|
||||||
71
lib/libc_r/man/sem_post.3
Normal file
71
lib/libc_r/man/sem_post.3
Normal file
@ -0,0 +1,71 @@
|
|||||||
|
.\" Copyright (C) 2000 Jason Evans <jasone@canonware.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(s), this list of conditions and the following disclaimer as
|
||||||
|
.\" the first lines of this file unmodified other than the possible
|
||||||
|
.\" addition of one or more copyright notices.
|
||||||
|
.\" 2. Redistributions in binary form must reproduce the above copyright
|
||||||
|
.\" notice(s), 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 COPYRIGHT HOLDER(S) ``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 COPYRIGHT HOLDER(S) 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.
|
||||||
|
.\"
|
||||||
|
.\" $FreeBSD$
|
||||||
|
.Dd February 15, 2000
|
||||||
|
.Dt SEM_POST 3
|
||||||
|
.Os
|
||||||
|
.Sh NAME
|
||||||
|
.Nm sem_post
|
||||||
|
.Nd increment (unlock) a semaphore
|
||||||
|
.Sh SYNOPSIS
|
||||||
|
.Fd #include <semaphore.h>
|
||||||
|
.Ft int
|
||||||
|
.Fn sem_post "sem_t *sem"
|
||||||
|
.Sh DESCRIPTION
|
||||||
|
The
|
||||||
|
.Fn sem_post
|
||||||
|
function increments (unlocks) the semaphore pointed to by
|
||||||
|
.Fa sem .
|
||||||
|
If there are threads blocked on the semaphore when
|
||||||
|
.Fn sem_post
|
||||||
|
is called, then the highest priority thread that has been blocked the longest on
|
||||||
|
the semaphore will be allowed to return from
|
||||||
|
.Fn sem_wait .
|
||||||
|
.Sh RETURN VALUES
|
||||||
|
If successful,
|
||||||
|
.Fn sem_post
|
||||||
|
returns 0. Otherwise, -1 is returned and
|
||||||
|
.Va errno
|
||||||
|
is set to indicate the type of
|
||||||
|
error.
|
||||||
|
.Sh ERRORS
|
||||||
|
.Fn sem_post
|
||||||
|
will fail if:
|
||||||
|
.Bl -tag -width Er
|
||||||
|
.It Bq Er EINVAL
|
||||||
|
.Fa sem
|
||||||
|
points to an invalid semaphore.
|
||||||
|
.El
|
||||||
|
.Sh SEE ALSO
|
||||||
|
.Xr sem_wait 3 ,
|
||||||
|
.Xr sem_trywait 3
|
||||||
|
.Sh STANDARDS
|
||||||
|
.Fn sem_post
|
||||||
|
conforms to ISO/IEC 9945-1 ANSI/IEEE
|
||||||
|
.Pq Dq Tn POSIX
|
||||||
|
Std 1003.1 1996 Edition.
|
||||||
92
lib/libc_r/man/sem_wait.3
Normal file
92
lib/libc_r/man/sem_wait.3
Normal file
@ -0,0 +1,92 @@
|
|||||||
|
.\" Copyright (C) 2000 Jason Evans <jasone@canonware.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(s), this list of conditions and the following disclaimer as
|
||||||
|
.\" the first lines of this file unmodified other than the possible
|
||||||
|
.\" addition of one or more copyright notices.
|
||||||
|
.\" 2. Redistributions in binary form must reproduce the above copyright
|
||||||
|
.\" notice(s), 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 COPYRIGHT HOLDER(S) ``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 COPYRIGHT HOLDER(S) 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.
|
||||||
|
.\"
|
||||||
|
.\" $FreeBSD$
|
||||||
|
.Dd February 15, 2000
|
||||||
|
.Dt SEM_WAIT 3
|
||||||
|
.Os
|
||||||
|
.Sh NAME
|
||||||
|
.Nm sem_wait ,
|
||||||
|
.Nm sem_trywait
|
||||||
|
.Nd decrement (lock) a semaphore
|
||||||
|
.Sh SYNOPSIS
|
||||||
|
.Fd #include <semaphore.h>
|
||||||
|
.Ft int
|
||||||
|
.Fn sem_wait "sem_t *sem"
|
||||||
|
.Ft int
|
||||||
|
.Fn sem_trywait "sem_t *sem"
|
||||||
|
.Sh DESCRIPTION
|
||||||
|
The
|
||||||
|
.Fn sem_wait
|
||||||
|
function decrements (locks) the semaphore pointed to by
|
||||||
|
.Fa sem ,
|
||||||
|
but blocks if the value of
|
||||||
|
.Fa sem
|
||||||
|
is zero, until the value is non-zero and the value can be decremented.
|
||||||
|
.Pp
|
||||||
|
The
|
||||||
|
.Fn sem_trywait
|
||||||
|
function decrements (locks) the semaphore pointed to by
|
||||||
|
.Fa sem
|
||||||
|
only if the value is non-zero. Otherwise, the semaphore is not decremented and
|
||||||
|
an error is returned.
|
||||||
|
.Sh RETURN VALUES
|
||||||
|
If successful,
|
||||||
|
.Fn sem_wait
|
||||||
|
and
|
||||||
|
.Fn sem_trywait
|
||||||
|
return 0. Otherwise, -1 is returned and
|
||||||
|
.Va errno
|
||||||
|
is set to indicate the type of
|
||||||
|
error.
|
||||||
|
.Sh ERRORS
|
||||||
|
.Fn sem_wait
|
||||||
|
and
|
||||||
|
.Fn sem_trywait
|
||||||
|
will fail if:
|
||||||
|
.Bl -tag -width Er
|
||||||
|
.It Bq Er EINVAL
|
||||||
|
.Fa sem
|
||||||
|
points to an invalid semaphore.
|
||||||
|
.El
|
||||||
|
.Pp
|
||||||
|
Additionally,
|
||||||
|
.Fn sem_trywait
|
||||||
|
will fail if:
|
||||||
|
.Bl -tag -width Er
|
||||||
|
.It Bq Er EAGAIN
|
||||||
|
The semaphore value was zero, and thus could not be decremented.
|
||||||
|
.El
|
||||||
|
.Sh SEE ALSO
|
||||||
|
.Xr sem_post 3
|
||||||
|
.Sh STANDARDS
|
||||||
|
.Fn sem_wait
|
||||||
|
and
|
||||||
|
.Fn sem_trywait
|
||||||
|
conform to ISO/IEC 9945-1 ANSI/IEEE
|
||||||
|
.Pq Dq Tn POSIX
|
||||||
|
Std 1003.1 1996 Edition.
|
||||||
@ -4,7 +4,8 @@
|
|||||||
|
|
||||||
.PATH: ${.CURDIR}/man
|
.PATH: ${.CURDIR}/man
|
||||||
|
|
||||||
MAN3+= pthread_cleanup_pop.3 \
|
MAN3+= pthread_cancel.3 \
|
||||||
|
pthread_cleanup_pop.3 \
|
||||||
pthread_cleanup_push.3 \
|
pthread_cleanup_push.3 \
|
||||||
pthread_cond_broadcast.3 \
|
pthread_cond_broadcast.3 \
|
||||||
pthread_cond_destroy.3 \
|
pthread_cond_destroy.3 \
|
||||||
@ -12,7 +13,6 @@ MAN3+= pthread_cleanup_pop.3 \
|
|||||||
pthread_cond_signal.3 \
|
pthread_cond_signal.3 \
|
||||||
pthread_cond_timedwait.3 \
|
pthread_cond_timedwait.3 \
|
||||||
pthread_cond_wait.3 \
|
pthread_cond_wait.3 \
|
||||||
pthread_cancel.3 \
|
|
||||||
pthread_create.3 \
|
pthread_create.3 \
|
||||||
pthread_detach.3 \
|
pthread_detach.3 \
|
||||||
pthread_equal.3 \
|
pthread_equal.3 \
|
||||||
@ -38,7 +38,16 @@ MAN3+= pthread_cleanup_pop.3 \
|
|||||||
pthread_rwlockattr_setpshared.3 \
|
pthread_rwlockattr_setpshared.3 \
|
||||||
pthread_self.3 \
|
pthread_self.3 \
|
||||||
pthread_setspecific.3 \
|
pthread_setspecific.3 \
|
||||||
pthread_testcancel.3
|
pthread_testcancel.3 \
|
||||||
|
sem_destroy.3 \
|
||||||
|
sem_getvalue.3 \
|
||||||
|
sem_init.3 \
|
||||||
|
sem_open.3 \
|
||||||
|
sem_post.3 \
|
||||||
|
sem_wait.3
|
||||||
|
|
||||||
MLINKS+= pthread_cancel.3 pthread_setcancelstate.3 \
|
MLINKS+= pthread_cancel.3 pthread_setcancelstate.3 \
|
||||||
pthread_cancel.3 pthread_getcancelstate.3
|
pthread_cancel.3 pthread_getcancelstate.3 \
|
||||||
|
sem_open.3 sem_close.3 \
|
||||||
|
sem_open.3 sem_unlink.3 \
|
||||||
|
sem_wait.3 sem_trywait.3
|
||||||
|
|||||||
83
lib/libpthread/man/sem_destroy.3
Normal file
83
lib/libpthread/man/sem_destroy.3
Normal file
@ -0,0 +1,83 @@
|
|||||||
|
.\" Copyright (C) 2000 Jason Evans <jasone@canonware.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(s), this list of conditions and the following disclaimer as
|
||||||
|
.\" the first lines of this file unmodified other than the possible
|
||||||
|
.\" addition of one or more copyright notices.
|
||||||
|
.\" 2. Redistributions in binary form must reproduce the above copyright
|
||||||
|
.\" notice(s), 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 COPYRIGHT HOLDER(S) ``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 COPYRIGHT HOLDER(S) 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.
|
||||||
|
.\"
|
||||||
|
.\" $FreeBSD$
|
||||||
|
.Dd February 15, 2000
|
||||||
|
.Dt SEM_DESTROY 3
|
||||||
|
.Os
|
||||||
|
.Sh NAME
|
||||||
|
.Nm sem_destroy
|
||||||
|
.Nd destroy an unnamed semaphore
|
||||||
|
.Sh SYNOPSIS
|
||||||
|
.Fd #include <semaphore.h>
|
||||||
|
.Ft int
|
||||||
|
.Fn sem_destroy "sem_t *sem"
|
||||||
|
.Sh DESCRIPTION
|
||||||
|
The
|
||||||
|
.Fn sem_destroy
|
||||||
|
function destroys the unnamed semaphore pointed to by
|
||||||
|
.Fa sem .
|
||||||
|
After a successful call to
|
||||||
|
.Fn sem_destroy ,
|
||||||
|
.Fa sem
|
||||||
|
is unuseable until re-initialized by another call to
|
||||||
|
.Fn sem_init .
|
||||||
|
.Sh RETURN VALUES
|
||||||
|
If successful,
|
||||||
|
.Fn sem_destroy
|
||||||
|
returns 0. Otherwise, -1 is returned and
|
||||||
|
.Va errno
|
||||||
|
is set to indicate the type of
|
||||||
|
error.
|
||||||
|
.Sh ERRORS
|
||||||
|
.Fn sem_destroy
|
||||||
|
will fail if:
|
||||||
|
.Bl -tag -width Er
|
||||||
|
.It Bq Er EINVAL
|
||||||
|
.Fa sem
|
||||||
|
points to an invalid semaphore.
|
||||||
|
.It Bq Er EBUSY
|
||||||
|
There are currently threads blocked on the semaphore that
|
||||||
|
.Fa sem
|
||||||
|
points to.
|
||||||
|
.El
|
||||||
|
.Sh SEE ALSO
|
||||||
|
.Xr sem_init 3
|
||||||
|
.Sh STANDARDS
|
||||||
|
.Fn sem_destroy
|
||||||
|
conforms to ISO/IEC 9945-1 ANSI/IEEE
|
||||||
|
.Pq Dq Tn POSIX
|
||||||
|
Std 1003.1 1996 Edition.
|
||||||
|
.Pp
|
||||||
|
POSIX does not define the behavior of
|
||||||
|
.Fn sem_destroy
|
||||||
|
if called while there are threads blocked on
|
||||||
|
.Fa sem ,
|
||||||
|
but this implementation is guaranteed to return -1 and set
|
||||||
|
.Va errno
|
||||||
|
to EBUSY if there are threads blocked on
|
||||||
|
.Fa sem .
|
||||||
77
lib/libpthread/man/sem_getvalue.3
Normal file
77
lib/libpthread/man/sem_getvalue.3
Normal file
@ -0,0 +1,77 @@
|
|||||||
|
.\" Copyright (C) 2000 Jason Evans <jasone@canonware.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(s), this list of conditions and the following disclaimer as
|
||||||
|
.\" the first lines of this file unmodified other than the possible
|
||||||
|
.\" addition of one or more copyright notices.
|
||||||
|
.\" 2. Redistributions in binary form must reproduce the above copyright
|
||||||
|
.\" notice(s), 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 COPYRIGHT HOLDER(S) ``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 COPYRIGHT HOLDER(S) 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.
|
||||||
|
.\"
|
||||||
|
.\" $FreeBSD$
|
||||||
|
.Dd February 15, 2000
|
||||||
|
.Dt SEM_GETVALUE 3
|
||||||
|
.Os
|
||||||
|
.Sh NAME
|
||||||
|
.Nm sem_getvalue
|
||||||
|
.Nd get the value of a semaphore
|
||||||
|
.Sh SYNOPSIS
|
||||||
|
.Fd #include <semaphore.h>
|
||||||
|
.Ft int
|
||||||
|
.Fn sem_getvalue "sem_t *sem" "int *sval"
|
||||||
|
.Sh DESCRIPTION
|
||||||
|
The
|
||||||
|
.Fn sem_getvalue
|
||||||
|
function sets the variable pointed to by
|
||||||
|
.Fa sval
|
||||||
|
to the current value of the semaphore pointed to by
|
||||||
|
.Fa sem ,
|
||||||
|
as of the time that the call to
|
||||||
|
.Fn sem_getvalue
|
||||||
|
is actually run.
|
||||||
|
.Sh RETURN VALUES
|
||||||
|
If successful,
|
||||||
|
.Fn sem_getvalue
|
||||||
|
returns 0. Otherwise, -1 is returned and
|
||||||
|
.Va errno
|
||||||
|
is set to indicate the type of
|
||||||
|
error.
|
||||||
|
.Sh ERRORS
|
||||||
|
.Fn sem_getvalue
|
||||||
|
will fail if:
|
||||||
|
.Bl -tag -width Er
|
||||||
|
.It Bq Er EINVAL
|
||||||
|
.Fa sem
|
||||||
|
points to an invalid semaphore.
|
||||||
|
.El
|
||||||
|
.Sh SEE ALSO
|
||||||
|
.Xr sem_post 3 ,
|
||||||
|
.Xr sem_wait 3 ,
|
||||||
|
.Xr sem_trywait 3
|
||||||
|
.Sh STANDARDS
|
||||||
|
.Fn sem_getvalue
|
||||||
|
conforms to ISO/IEC 9945-1 ANSI/IEEE
|
||||||
|
.Pq Dq Tn POSIX
|
||||||
|
Std 1003.1 1996 Edition.
|
||||||
|
.Pp
|
||||||
|
The value of the semaphore is never negative, even if there are threads blocked
|
||||||
|
on the semaphore. POSIX is somewhat ambiguous in its wording with regard to
|
||||||
|
what the value of the semaphore should be if there are blocked waiting threads,
|
||||||
|
but this behavior is conformant, given the wording of the specification.
|
||||||
100
lib/libpthread/man/sem_init.3
Normal file
100
lib/libpthread/man/sem_init.3
Normal file
@ -0,0 +1,100 @@
|
|||||||
|
.\" Copyright (C) 2000 Jason Evans <jasone@canonware.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(s), this list of conditions and the following disclaimer as
|
||||||
|
.\" the first lines of this file unmodified other than the possible
|
||||||
|
.\" addition of one or more copyright notices.
|
||||||
|
.\" 2. Redistributions in binary form must reproduce the above copyright
|
||||||
|
.\" notice(s), 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 COPYRIGHT HOLDER(S) ``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 COPYRIGHT HOLDER(S) 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.
|
||||||
|
.\"
|
||||||
|
.\" $FreeBSD$
|
||||||
|
.Dd February 15, 2000
|
||||||
|
.Dt SEM_INIT 3
|
||||||
|
.Os
|
||||||
|
.Sh NAME
|
||||||
|
.Nm sem_init
|
||||||
|
.Nd initialize an unnamed semaphore
|
||||||
|
.Sh SYNOPSIS
|
||||||
|
.Fd #include <semaphore.h>
|
||||||
|
.Ft int
|
||||||
|
.Fn sem_init "sem_t *sem" "int pshared" "unsigned int value"
|
||||||
|
.Sh DESCRIPTION
|
||||||
|
The
|
||||||
|
.Fn sem_init
|
||||||
|
function initializes the unnamed semaphore pointed to by
|
||||||
|
.Fa sem
|
||||||
|
to have the value
|
||||||
|
.Fa value .
|
||||||
|
A non-zero value for
|
||||||
|
.Fa pshared
|
||||||
|
specifies a shared semaphore that can be used by multiple processes, which this
|
||||||
|
implementation is not capable of.
|
||||||
|
.Pp
|
||||||
|
Following a successful call to
|
||||||
|
.Fn sem_init ,
|
||||||
|
.Fa sem
|
||||||
|
can be used as an argument in subsequent calls to
|
||||||
|
.Fa sem_wait ,
|
||||||
|
.Fa sem_trywait ,
|
||||||
|
.Fa sem_post ,
|
||||||
|
and
|
||||||
|
.Fa sem_destroy .
|
||||||
|
.Fa sem
|
||||||
|
is no longer valid after a successful call to
|
||||||
|
.Fa sem_destroy .
|
||||||
|
.Sh RETURN VALUES
|
||||||
|
If successful,
|
||||||
|
.Fn sem_init
|
||||||
|
returns 0. Otherwise, -1 is returned and
|
||||||
|
.Va errno
|
||||||
|
is set to indicate the type of
|
||||||
|
error.
|
||||||
|
.Sh ERRORS
|
||||||
|
.Fn sem_init
|
||||||
|
will fail if:
|
||||||
|
.Bl -tag -width Er
|
||||||
|
.It Bq Er EINVAL
|
||||||
|
.Fa value
|
||||||
|
exceeds SEM_VALUE_MAX.
|
||||||
|
.It Bq Er ENOSPC
|
||||||
|
Memory allocation error.
|
||||||
|
.It Bq Er EPERM
|
||||||
|
Unable to initialize a shared semaphore.
|
||||||
|
.El
|
||||||
|
.Sh SEE ALSO
|
||||||
|
.Xr sem_wait 3 ,
|
||||||
|
.Xr sem_trywait 3 ,
|
||||||
|
.Xr sem_post 3 ,
|
||||||
|
.Xr sem_destroy
|
||||||
|
.Sh STANDARDS
|
||||||
|
.Fn sem_init
|
||||||
|
conforms to ISO/IEC 9945-1 ANSI/IEEE
|
||||||
|
.Pq Dq Tn POSIX
|
||||||
|
Std 1003.1 1996 Edition.
|
||||||
|
.Pp
|
||||||
|
This implementation does not support shared semaphores, and reports this fact
|
||||||
|
by setting
|
||||||
|
.Va errno
|
||||||
|
to EPERM. This is perhaps a stretch of the intention of POSIX, but is
|
||||||
|
compliant, with the caveat that
|
||||||
|
.Fn sem_init
|
||||||
|
always reports a permissions error when an attempt to create a shared semaphore
|
||||||
|
is made.
|
||||||
80
lib/libpthread/man/sem_open.3
Normal file
80
lib/libpthread/man/sem_open.3
Normal file
@ -0,0 +1,80 @@
|
|||||||
|
.\" Copyright (C) 2000 Jason Evans <jasone@canonware.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(s), this list of conditions and the following disclaimer as
|
||||||
|
.\" the first lines of this file unmodified other than the possible
|
||||||
|
.\" addition of one or more copyright notices.
|
||||||
|
.\" 2. Redistributions in binary form must reproduce the above copyright
|
||||||
|
.\" notice(s), 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 COPYRIGHT HOLDER(S) ``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 COPYRIGHT HOLDER(S) 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.
|
||||||
|
.\"
|
||||||
|
.\" $FreeBSD$
|
||||||
|
.Dd February 15, 2000
|
||||||
|
.Dt SEM_OPEN 3
|
||||||
|
.Os
|
||||||
|
.Sh NAME
|
||||||
|
.Nm sem_open ,
|
||||||
|
.Nm sem_close ,
|
||||||
|
.Nm sem_unlink
|
||||||
|
.Nd named semaphore operations
|
||||||
|
.Sh SYNOPSIS
|
||||||
|
.Fd #include <semaphore.h>
|
||||||
|
.Ft sem_t *
|
||||||
|
.Fn sem_open "const char *name" "int oflag" "..."
|
||||||
|
.Ft int
|
||||||
|
.Fn sem_close "sem_t *sem"
|
||||||
|
.Ft int
|
||||||
|
.Fn sem_unlink "const char *name"
|
||||||
|
.Sh DESCRIPTION
|
||||||
|
The
|
||||||
|
.Fn sem_open ,
|
||||||
|
.Fn sem_close ,
|
||||||
|
and
|
||||||
|
.Fn sem_unlink
|
||||||
|
functions are not supported by this implementation.
|
||||||
|
.Sh RETURN VALUES
|
||||||
|
.Fn sem_open
|
||||||
|
returns SEM_FAILED and sets
|
||||||
|
.Va errno
|
||||||
|
to indicate an error.
|
||||||
|
.Fn sem_close
|
||||||
|
and
|
||||||
|
.Fn sem_unlink
|
||||||
|
return -1 and set
|
||||||
|
.Va errno
|
||||||
|
to indicate an error.
|
||||||
|
.Sh ERRORS
|
||||||
|
.Fn sem_open ,
|
||||||
|
.Fn sem_close ,
|
||||||
|
and
|
||||||
|
.Fn sem_unlink
|
||||||
|
will fail:
|
||||||
|
.Bl -tag -width Er
|
||||||
|
.It Bq Er ENOSYS
|
||||||
|
Function not supported by this implementation.
|
||||||
|
.El
|
||||||
|
.Sh STANDARDS
|
||||||
|
.Fn sem_open ,
|
||||||
|
.Fn sem_close ,
|
||||||
|
and
|
||||||
|
.Fn sem_unlink
|
||||||
|
conform to ISO/IEC 9945-1 ANSI/IEEE
|
||||||
|
.Pq Dq Tn POSIX
|
||||||
|
Std 1003.1 1996 Edition.
|
||||||
71
lib/libpthread/man/sem_post.3
Normal file
71
lib/libpthread/man/sem_post.3
Normal file
@ -0,0 +1,71 @@
|
|||||||
|
.\" Copyright (C) 2000 Jason Evans <jasone@canonware.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(s), this list of conditions and the following disclaimer as
|
||||||
|
.\" the first lines of this file unmodified other than the possible
|
||||||
|
.\" addition of one or more copyright notices.
|
||||||
|
.\" 2. Redistributions in binary form must reproduce the above copyright
|
||||||
|
.\" notice(s), 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 COPYRIGHT HOLDER(S) ``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 COPYRIGHT HOLDER(S) 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.
|
||||||
|
.\"
|
||||||
|
.\" $FreeBSD$
|
||||||
|
.Dd February 15, 2000
|
||||||
|
.Dt SEM_POST 3
|
||||||
|
.Os
|
||||||
|
.Sh NAME
|
||||||
|
.Nm sem_post
|
||||||
|
.Nd increment (unlock) a semaphore
|
||||||
|
.Sh SYNOPSIS
|
||||||
|
.Fd #include <semaphore.h>
|
||||||
|
.Ft int
|
||||||
|
.Fn sem_post "sem_t *sem"
|
||||||
|
.Sh DESCRIPTION
|
||||||
|
The
|
||||||
|
.Fn sem_post
|
||||||
|
function increments (unlocks) the semaphore pointed to by
|
||||||
|
.Fa sem .
|
||||||
|
If there are threads blocked on the semaphore when
|
||||||
|
.Fn sem_post
|
||||||
|
is called, then the highest priority thread that has been blocked the longest on
|
||||||
|
the semaphore will be allowed to return from
|
||||||
|
.Fn sem_wait .
|
||||||
|
.Sh RETURN VALUES
|
||||||
|
If successful,
|
||||||
|
.Fn sem_post
|
||||||
|
returns 0. Otherwise, -1 is returned and
|
||||||
|
.Va errno
|
||||||
|
is set to indicate the type of
|
||||||
|
error.
|
||||||
|
.Sh ERRORS
|
||||||
|
.Fn sem_post
|
||||||
|
will fail if:
|
||||||
|
.Bl -tag -width Er
|
||||||
|
.It Bq Er EINVAL
|
||||||
|
.Fa sem
|
||||||
|
points to an invalid semaphore.
|
||||||
|
.El
|
||||||
|
.Sh SEE ALSO
|
||||||
|
.Xr sem_wait 3 ,
|
||||||
|
.Xr sem_trywait 3
|
||||||
|
.Sh STANDARDS
|
||||||
|
.Fn sem_post
|
||||||
|
conforms to ISO/IEC 9945-1 ANSI/IEEE
|
||||||
|
.Pq Dq Tn POSIX
|
||||||
|
Std 1003.1 1996 Edition.
|
||||||
92
lib/libpthread/man/sem_wait.3
Normal file
92
lib/libpthread/man/sem_wait.3
Normal file
@ -0,0 +1,92 @@
|
|||||||
|
.\" Copyright (C) 2000 Jason Evans <jasone@canonware.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(s), this list of conditions and the following disclaimer as
|
||||||
|
.\" the first lines of this file unmodified other than the possible
|
||||||
|
.\" addition of one or more copyright notices.
|
||||||
|
.\" 2. Redistributions in binary form must reproduce the above copyright
|
||||||
|
.\" notice(s), 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 COPYRIGHT HOLDER(S) ``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 COPYRIGHT HOLDER(S) 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.
|
||||||
|
.\"
|
||||||
|
.\" $FreeBSD$
|
||||||
|
.Dd February 15, 2000
|
||||||
|
.Dt SEM_WAIT 3
|
||||||
|
.Os
|
||||||
|
.Sh NAME
|
||||||
|
.Nm sem_wait ,
|
||||||
|
.Nm sem_trywait
|
||||||
|
.Nd decrement (lock) a semaphore
|
||||||
|
.Sh SYNOPSIS
|
||||||
|
.Fd #include <semaphore.h>
|
||||||
|
.Ft int
|
||||||
|
.Fn sem_wait "sem_t *sem"
|
||||||
|
.Ft int
|
||||||
|
.Fn sem_trywait "sem_t *sem"
|
||||||
|
.Sh DESCRIPTION
|
||||||
|
The
|
||||||
|
.Fn sem_wait
|
||||||
|
function decrements (locks) the semaphore pointed to by
|
||||||
|
.Fa sem ,
|
||||||
|
but blocks if the value of
|
||||||
|
.Fa sem
|
||||||
|
is zero, until the value is non-zero and the value can be decremented.
|
||||||
|
.Pp
|
||||||
|
The
|
||||||
|
.Fn sem_trywait
|
||||||
|
function decrements (locks) the semaphore pointed to by
|
||||||
|
.Fa sem
|
||||||
|
only if the value is non-zero. Otherwise, the semaphore is not decremented and
|
||||||
|
an error is returned.
|
||||||
|
.Sh RETURN VALUES
|
||||||
|
If successful,
|
||||||
|
.Fn sem_wait
|
||||||
|
and
|
||||||
|
.Fn sem_trywait
|
||||||
|
return 0. Otherwise, -1 is returned and
|
||||||
|
.Va errno
|
||||||
|
is set to indicate the type of
|
||||||
|
error.
|
||||||
|
.Sh ERRORS
|
||||||
|
.Fn sem_wait
|
||||||
|
and
|
||||||
|
.Fn sem_trywait
|
||||||
|
will fail if:
|
||||||
|
.Bl -tag -width Er
|
||||||
|
.It Bq Er EINVAL
|
||||||
|
.Fa sem
|
||||||
|
points to an invalid semaphore.
|
||||||
|
.El
|
||||||
|
.Pp
|
||||||
|
Additionally,
|
||||||
|
.Fn sem_trywait
|
||||||
|
will fail if:
|
||||||
|
.Bl -tag -width Er
|
||||||
|
.It Bq Er EAGAIN
|
||||||
|
The semaphore value was zero, and thus could not be decremented.
|
||||||
|
.El
|
||||||
|
.Sh SEE ALSO
|
||||||
|
.Xr sem_post 3
|
||||||
|
.Sh STANDARDS
|
||||||
|
.Fn sem_wait
|
||||||
|
and
|
||||||
|
.Fn sem_trywait
|
||||||
|
conform to ISO/IEC 9945-1 ANSI/IEEE
|
||||||
|
.Pq Dq Tn POSIX
|
||||||
|
Std 1003.1 1996 Edition.
|
||||||
Loading…
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Reference in New Issue
Block a user