| dllockinit.3 (108030) | dllockinit.3 (108087) |
|---|---|
| 1.\" 2.\" Copyright (c) 1999, 2000 John D. Polstra 3.\" All rights reserved. 4.\" 5.\" Redistribution and use in source and binary forms, with or without 6.\" modification, are permitted provided that the following conditions 7.\" are met: 8.\" 1. Redistributions of source code must retain the above copyright --- 9 unchanged lines hidden (view full) --- 18.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24.\" SUCH DAMAGE. 25.\" | 1.\" 2.\" Copyright (c) 1999, 2000 John D. Polstra 3.\" All rights reserved. 4.\" 5.\" Redistribution and use in source and binary forms, with or without 6.\" modification, are permitted provided that the following conditions 7.\" are met: 8.\" 1. Redistributions of source code must retain the above copyright --- 9 unchanged lines hidden (view full) --- 18.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24.\" SUCH DAMAGE. 25.\" |
| 26.\" $FreeBSD: head/lib/libc/gen/dllockinit.3 108030 2002-12-18 10:13:54Z ru $ | 26.\" $FreeBSD: head/lib/libc/gen/dllockinit.3 108087 2002-12-19 09:40:28Z ru $ |
| 27.\" 28.Dd July 5, 2000 29.Os 30.Dt DLLOCKINIT 3 31.Sh NAME 32.Nm dllockinit 33.Nd register thread locking methods with the dynamic linker 34.Sh LIBRARY --- 12 unchanged lines hidden (view full) --- 47Threads packages can call 48.Fn dllockinit 49at initialization time to register locking functions for the dynamic 50linker to use. This enables the dynamic linker to prevent multiple 51threads from entering its critical sections simultaneously. 52.Pp 53The 54.Fa context | 27.\" 28.Dd July 5, 2000 29.Os 30.Dt DLLOCKINIT 3 31.Sh NAME 32.Nm dllockinit 33.Nd register thread locking methods with the dynamic linker 34.Sh LIBRARY --- 12 unchanged lines hidden (view full) --- 47Threads packages can call 48.Fn dllockinit 49at initialization time to register locking functions for the dynamic 50linker to use. This enables the dynamic linker to prevent multiple 51threads from entering its critical sections simultaneously. 52.Pp 53The 54.Fa context |
| 55parameter specifies an opaque context for creating locks. The | 55argument specifies an opaque context for creating locks. The |
| 56dynamic linker will pass it to the 57.Fa lock_create 58function when creating the locks it needs. When the dynamic linker 59is permanently finished using the locking functions (e.g., if the 60program makes a subsequent call to 61.Fn dllockinit 62to register new locking functions) it will call 63.Fa context_destroy 64to destroy the context. 65.Pp 66The 67.Fa lock_create | 56dynamic linker will pass it to the 57.Fa lock_create 58function when creating the locks it needs. When the dynamic linker 59is permanently finished using the locking functions (e.g., if the 60program makes a subsequent call to 61.Fn dllockinit 62to register new locking functions) it will call 63.Fa context_destroy 64to destroy the context. 65.Pp 66The 67.Fa lock_create |
| 68parameter specifies a function for creating a read/write lock. It | 68argument specifies a function for creating a read/write lock. It |
| 69must return a pointer to the new lock. 70.Pp 71The 72.Fa rlock_acquire 73and 74.Fa wlock_acquire | 69must return a pointer to the new lock. 70.Pp 71The 72.Fa rlock_acquire 73and 74.Fa wlock_acquire |
| 75parameters specify functions which lock a lock for reading or | 75arguments specify functions which lock a lock for reading or |
| 76writing, respectively. The 77.Fa lock_release | 76writing, respectively. The 77.Fa lock_release |
| 78parameter specifies a function which unlocks a lock. Each of these | 78argument specifies a function which unlocks a lock. Each of these |
| 79functions is passed a pointer to the lock. 80.Pp 81The 82.Fa lock_destroy | 79functions is passed a pointer to the lock. 80.Pp 81The 82.Fa lock_destroy |
| 83parameter specifies a function to destroy a lock. It may be | 83argument specifies a function to destroy a lock. It may be |
| 84.Dv NULL 85if locks do not need to be destroyed. The 86.Fa context_destroy | 84.Dv NULL 85if locks do not need to be destroyed. The 86.Fa context_destroy |
| 87parameter specifies a function to destroy the context. It may be | 87argument specifies a function to destroy the context. It may be |
| 88.Dv NULL 89if the context does not need to be destroyed. 90.Pp 91Until 92.Fn dllockinit 93is called, the dynamic linker protects its critical sections using 94a default locking mechanism which works by blocking the 95.Dv SIGVTALRM , --- 20 unchanged lines hidden --- | 88.Dv NULL 89if the context does not need to be destroyed. 90.Pp 91Until 92.Fn dllockinit 93is called, the dynamic linker protects its critical sections using 94a default locking mechanism which works by blocking the 95.Dv SIGVTALRM , --- 20 unchanged lines hidden --- |