From owner-cvs-all Wed Oct 23 11:14: 9 2002 Delivered-To: cvs-all@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 8DD1137B401; Wed, 23 Oct 2002 11:14:07 -0700 (PDT) Received: from khavrinen.lcs.mit.edu (khavrinen.lcs.mit.edu [18.24.4.193]) by mx1.FreeBSD.org (Postfix) with ESMTP id E586A43E3B; Wed, 23 Oct 2002 11:14:06 -0700 (PDT) (envelope-from wollman@khavrinen.lcs.mit.edu) Received: from khavrinen.lcs.mit.edu (localhost [IPv6:::1]) by khavrinen.lcs.mit.edu (8.12.3/8.12.5) with ESMTP id g9NIE3gQ097648 (version=TLSv1/SSLv3 cipher=EDH-RSA-DES-CBC3-SHA bits=168 verify=OK); Wed, 23 Oct 2002 14:14:03 -0400 (EDT) (envelope-from wollman@khavrinen.lcs.mit.edu) Received: (from wollman@localhost) by khavrinen.lcs.mit.edu (8.12.3/8.12.5/Submit) id g9NIE3to097645; Wed, 23 Oct 2002 14:14:03 -0400 (EDT) (envelope-from wollman) Date: Wed, 23 Oct 2002 14:14:03 -0400 (EDT) From: Garrett Wollman Message-Id: <200210231814.g9NIE3to097645@khavrinen.lcs.mit.edu> To: Craig Rodrigues Cc: cvs-committers@FreeBSD.org, cvs-all@FreeBSD.org Subject: Re: cvs commit: src/lib/libc/sys aio_cancel.2 aio_error.2 aio_read.2 aio_return.2 aio_suspend.2 aio_waitcomplete.2 aio_write.2 In-Reply-To: <20021023110619.A27272@attbi.com> References: <200210221612.g9MGCR1p012070@repoman.freebsd.org> <20021022161820.GA57732@starjuice.net> <20021022164649.GS91539@elvis.mu.org> <20021022132829.A22126@attbi.com> <20021023110619.A27272@attbi.com> Sender: owner-cvs-all@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG < said: > +.Sh KERNEL OPTIONS [...] .Sh APPLICATION USAGE Asynchronous I/O is specified as an option in .St -p1003.1-2001 and earlier standards. A portable application must be prepared for the possibility that asynchronous I/O may not be available, and also that it may not be available at run-time for certain files or types of file descriptors. .Pp The .Dv _POSIX_ASYNCHRONOUS_IO macro in .In unistd.h describes the compile-time support for .Nm . The following conditions are possible: .Bl -inset -offset indent .It Dv _POSIX_ASYNCHRONOUS_IO No is not defined . The implementation provides no information about whether programs using .Nm can be compiled. .It Dv _POSIX_ASYNCHRONOUS_IO No is defined to \-1 . The implementation does not support the asynchronous I/O feature; the .In aio.h header file and .Fn aio_* functions are not provided. .It Dv _POSIX_ASYNCHRONOUS_IO No is defined to a positive integer . The implementation supports the asynchronous I/O feature unconditionally, for all files and all file descriptors. The .In aio.h header file and .Fn aio_* functions are provided. .It Dv _POSIX_ASYNCHRONOUS_IO No is defined to zero . The implementation optionally supports asynchronous I/O. The .In aio.h header file and .Fn aio_* functions are provided. However, the result of calling any .Fn aio_* function is undefined unless the application has checked that the asynchronous I/O option is supported on the files or file descriptors it plans to use, by calling the .Xr pathconf 2 or .Xr fpathconf 2 function with a .Fa name argument of .Dv _PC_ASYNC_IO . If .Nm is available for the specified file (or descriptor), .Xr pathconf 2 (or .Xr fpathconf 2 ) will return a positive integer which is equal to the value specified for .Dv _POSIX_VERSION by the version of the standard the system implements. .El .Pp These configuration parameters can be queried by shell scripts using the .Xr getconf 1 program. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe cvs-all" in the body of the message