diff options
Diffstat (limited to 'lib/libc/sys/aio_cancel.2')
-rw-r--r-- | lib/libc/sys/aio_cancel.2 | 67 |
1 files changed, 49 insertions, 18 deletions
diff --git a/lib/libc/sys/aio_cancel.2 b/lib/libc/sys/aio_cancel.2 index 275c3eb..edec2e9 100644 --- a/lib/libc/sys/aio_cancel.2 +++ b/lib/libc/sys/aio_cancel.2 @@ -24,7 +24,7 @@ .\" .\" $FreeBSD$ .\" -.Dd June 2, 1999 +.Dd January 19, 2000 .Dt AIO_CANCEL 2 .Os .Sh NAME @@ -33,21 +33,41 @@ .Sh SYNOPSIS .Fd #include <aio.h> .Ft int -.Fn aio_cancel "int something" "struct aiocb * iocb" +.Fn aio_cancel "int fildes" "struct aiocb * iocb" .Sh DESCRIPTION The .Fn aio_cancel -function is supposed to cancel the specified outstanding asynchronous -I/O request. +function cancels the outstanding asynchronous +I/O request for the file descriptor specified in +.Ar fildes . +If +.Ar iocb +is specified, only that specific asynchronous I/O request is cancelled. +.Pp +Normal asynchronous notification occurs for cancelled requests. Requests +complete with an error result of +.Dv ECANCELED . +.Sh RESTRICTIONS +The +.Fn aio_cancel +function does not cancel asynchronous I/O requests for raw disk devices. The .Fn aio_cancel -is not implemented at this time, and always fails returning -.Dv ENOSYS . +function will always return +.Dv AIO_NOTCANCELED +for file descriptors associated with raw disk devices. .Sh RETURN VALUES -When +The .Fn aio_cancel -inevitably fails, it returns -.Dv ENOSYS -to signify it is not supported. +function returns -1 to indicate an error, or one of the following: +.Bl -tag -width Dv +.It Bq Dv AIO_CANCELED +All outstanding requests meeting the criteria specified were cancelled. +.It Bq Dv AIO_NOTCANCELED +Some requests were not cancelled, status for the requests should be +checked with aio_error(2). +.It Bq Dv AIO_ALLDONE +All of the requests meeting the criteria have finished. +.El .Sh SEE ALSO .Xr aio_error 2 , .Xr aio_read 2 , @@ -55,24 +75,35 @@ to signify it is not supported. .Xr aio_suspend 2 , .Xr aio_write 2 . .Sh ERRORS -The +An error return from .Fn aio_cancel -function currently always fails, due to: +indicates: .Bl -tag -width Er -.It Bq Er ENOSYS -this operation is not implemented at this time. +.It Bq Er EBADF +.Ar fildes +is an invalid file descriptor. .El .Sh STANDARDS -.Nm -fails to conform to the +The +.Fn aio_cancel +function is expected to conform to the .St -p1003.2 standard. .Sh HISTORY The -.Nm +.Fn aio_cancel function first appeared in .Fx 3.0 . +The first functional implemenation of +.Fn aio_cancel +appeared in +.Fx 4.0 . .Sh AUTHORS This -manual page was written by +manual page was originally written by .An Wes Peters Aq wes@softweyr.com . +.An Christopher M Sedore Aq cmsedore@maxwell.syr.edu +updated it when +.Fn aio_cancel +was implemented for FreeBSD 4.0. + |