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Diffstat (limited to 'static/freebsd/man2/lio_listio.2')
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diff --git a/static/freebsd/man2/lio_listio.2 b/static/freebsd/man2/lio_listio.2 new file mode 100644 index 00000000..bda65c38 --- /dev/null +++ b/static/freebsd/man2/lio_listio.2 @@ -0,0 +1,248 @@ +.\" Copyright (c) 2003 Tim J. Robbins +.\" 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 AUTHOR AND CONTRIBUTORS ``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 AUTHOR OR CONTRIBUTORS 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 January 13, 2024 +.Dt LIO_LISTIO 2 +.Os +.Sh NAME +.Nm lio_listio +.Nd "list directed I/O (REALTIME)" +.Sh LIBRARY +.Lb libc +.Sh SYNOPSIS +.In aio.h +.Ft int +.Fo lio_listio +.Fa "int mode" +.Fa "struct aiocb * const list[]" +.Fa "int nent" +.Fa "struct sigevent *sig" +.Fc +.Sh DESCRIPTION +The +.Fn lio_listio +function initiates a list of I/O requests with a single function call. +The +.Fa list +argument is an array of pointers to +.Vt aiocb +structures describing each operation to perform, +with +.Fa nent +elements. +.Dv NULL +elements are ignored. +.Pp +The +.Va aio_lio_opcode +field of each +.Vt aiocb +specifies the operation to be performed. +The following operations are supported: +.Bl -tag -width ".Dv LIO_WRITE" +.It Dv LIO_READ +Read data as if by a call to +.Xr aio_read 2 . +.It Dv LIO_READV +Read data as if by a call to +.Xr aio_readv 2 . +.It Dv LIO_NOP +No operation. +.It Dv LIO_WRITE +Write data as if by a call to +.Xr aio_write 2 . +.It Dv LIO_WRITEV +Write data as if by a call to +.Xr aio_writev 2 . +.El +.Pp +If the +.Dv LIO_READ , +.Dv LIO_READV , +.Dv LIO_WRITE , +.Dv LIO_WRITEV +opcodes are or-ed with the +.Dv LIO_FOFFSET +flag, the corresponding read or write operation uses the current file +descriptor offset instead of +.Va aio_offset +from +.Vt aiocb . +.Pp +If the +.Fa mode +argument is +.Dv LIO_WAIT , +.Fn lio_listio +does not return until all the requested operations have been completed. +If +.Fa mode +is +.Dv LIO_NOWAIT , +.Fa sig +can be used to request asynchronous notification when all operations have +completed. +If +.Fa sig +is +.Dv NULL , +no notification is sent. +.Pp +For +.Dv SIGEV_KEVENT +notifications, +the posted kevent will contain: +.Bl -column ".Va filter" +.It Sy Member Ta Sy Value +.It Va ident Ta Fa list +.It Va filter Ta Dv EVFILT_LIO +.It Va udata Ta +value stored in +.Fa sig->sigev_value +.El +.Pp +For +.Dv SIGEV_SIGNO +and +.Dv SIGEV_THREAD_ID +notifications, +the information for the queued signal will include +.Dv SI_ASYNCIO +in the +.Va si_code +field and the value stored in +.Fa sig->sigev_value +in the +.Va si_value +field. +.Pp +For +.Dv SIGEV_THREAD +notifications, +the value stored in +.Fa sig->sigev_value +is passed to the +.Fa sig->sigev_notify_function +as described in +.Xr sigevent 3 . +.Pp +The order in which the requests are carried out is not specified; +in particular, there is no guarantee that they will be executed in +the order 0, 1, ..., +.Fa nent Ns \-1 . +.Sh RETURN VALUES +If +.Fa mode +is +.Dv LIO_WAIT , +the +.Fn lio_listio +function returns 0 if the operations completed successfully, +otherwise \-1. +.Pp +If +.Fa mode +is +.Dv LIO_NOWAIT , +the +.Fn lio_listio +function returns 0 if the operations are successfully queued, +otherwise \-1. +.Sh ERRORS +The +.Fn lio_listio +function will fail if: +.Bl -tag -width Er +.It Bq Er EAGAIN +There are not enough resources to enqueue the requests. +.It Bq Er EAGAIN +The request would cause the system-wide limit +.Dv {AIO_MAX} +to be exceeded. +.It Bq Er EINVAL +The +.Fa mode +argument is neither +.Dv LIO_WAIT +nor +.Dv LIO_NOWAIT , +or +.Fa nent +is greater than +.Dv {AIO_LISTIO_MAX} . +.It Bq Er EINVAL +The asynchronous notification method in +.Fa sig->sigev_notify +is invalid or not supported. +.It Bq Er EINTR +A signal interrupted the system call before it could be completed. +.It Bq Er EIO +One or more requests failed. +.El +.Pp +In addition, the +.Fn lio_listio +function may fail for any of the reasons listed for +.Xr aio_read 2 +and +.Xr aio_write 2 . +.Pp +If +.Fn lio_listio +succeeds, or fails with an error code of +.Er EAGAIN , EINTR , +or +.Er EIO , +some of the requests may have been initiated. +The caller should check the error status of each +.Vt aiocb +structure individually by calling +.Xr aio_error 2 . +.Sh SEE ALSO +.Xr aio_error 2 , +.Xr aio_read 2 , +.Xr aio_readv 2 , +.Xr aio_write 2 , +.Xr aio_writev 2 , +.Xr read 2 , +.Xr write 2 , +.Xr sigevent 3 , +.Xr siginfo 3 , +.Xr aio 4 +.Sh STANDARDS +The +.Fn lio_listio +function is expected to conform to +.St -p1003.1-2001 . +The +.Dv LIO_READV +and +.Dv LIO_WRITEV +operations are +.Fx extensions, and should not be used in portable code. +.Sh HISTORY +The +.Fn lio_listio +system call first appeared in +.Fx 3.0 . |