diff options
author | tjr <tjr@FreeBSD.org> | 2003-01-12 09:28:16 +0000 |
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committer | tjr <tjr@FreeBSD.org> | 2003-01-12 09:28:16 +0000 |
commit | 727a92d7cbecfc93f89638cc64c4732bb1334c8f (patch) | |
tree | 41f68f3f7552fd5f5646ad1e89c0b8d5575264dc /lib/libc/sys | |
parent | 5f62aca2770374c1372d8c9cfcf084365983f321 (diff) | |
download | FreeBSD-src-727a92d7cbecfc93f89638cc64c4732bb1334c8f.zip FreeBSD-src-727a92d7cbecfc93f89638cc64c4732bb1334c8f.tar.gz |
Add a manual page for the lio_listio() syscall. Still needs a bit
of polishing.
Diffstat (limited to 'lib/libc/sys')
-rw-r--r-- | lib/libc/sys/Makefile.inc | 3 | ||||
-rw-r--r-- | lib/libc/sys/lio_listio.2 | 175 |
2 files changed, 177 insertions, 1 deletions
diff --git a/lib/libc/sys/Makefile.inc b/lib/libc/sys/Makefile.inc index 257ef7a..122d4ae 100644 --- a/lib/libc/sys/Makefile.inc +++ b/lib/libc/sys/Makefile.inc @@ -67,7 +67,8 @@ MAN+= _exit.2 accept.2 access.2 acct.2 adjtime.2 \ getsockopt.2 gettimeofday.2 getuid.2 \ intro.2 ioctl.2 issetugid.2 jail.2 kenv.2 kill.2 \ kldfind.2 kldfirstmod.2 kldload.2 kldnext.2 kldstat.2 kldsym.2 \ - kldunload.2 kqueue.2 kse.2 ktrace.2 link.2 listen.2 lseek.2 \ + kldunload.2 kqueue.2 kse.2 ktrace.2 link.2 lio_listio.2 listen.2 \ + lseek.2 \ madvise.2 mincore.2 minherit.2 mkdir.2 mkfifo.2 mknod.2 mlock.2 mmap.2 \ modfind.2 modnext.2 modstat.2 \ mount.2 mprotect.2 msync.2 munmap.2 nanosleep.2 \ diff --git a/lib/libc/sys/lio_listio.2 b/lib/libc/sys/lio_listio.2 new file mode 100644 index 0000000..fdb09f7 --- /dev/null +++ b/lib/libc/sys/lio_listio.2 @@ -0,0 +1,175 @@ +.\" 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. +.\" +.\" $FreeBSD$ +.\" +.Dd January 12, 2003 +.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_NOP +No operation. +.It Dv LIO_WRITE +Write data as if by a call to +.Xr aio_write 2 . +.El +.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 , +the requests are processed asynchronously and the signal specified by +.Fa sig +is sent when all operations have completed. +If +.Fa sig +is +.Dv NULL , +the calling process is not notified of I/O completion. +.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 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 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 , +.Er 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_write 2 , +.Xr read 2 , +.Xr write 2 , +.Xr aio 4 +.Sh STANDARDS +The +.Fn lio_listio +function is expected to conform to +.St -p1003.1-2001 . |