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diff --git a/libm/man/feclearexcept.3 b/libm/man/feclearexcept.3 new file mode 100644 index 0000000..073de67 --- /dev/null +++ b/libm/man/feclearexcept.3 @@ -0,0 +1,139 @@ +.\" Copyright (c) 2004 David Schultz <das@FreeBSD.org> +.\" 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: src/lib/msun/man/feclearexcept.3,v 1.3 2005/01/14 09:12:05 ru Exp $ +.\" +.Dd May 8, 2004 +.Dt FECLEAREXCEPT 3 +.Os +.Sh NAME +.Nm feclearexcept , +.Nm fegetexceptflag , +.Nm feraiseexcept , +.Nm fesetexceptflag , +.Nm fetestexcept +.Nd floating-point exception flag manipulation +.Sh LIBRARY +.Lb libm +.Sh SYNOPSIS +.In fenv.h +.Fd "#pragma STDC FENV_ACCESS ON" +.Ft int +.Fn feclearexcept "int excepts" +.Ft int +.Fn fegetexceptflag "fexcept_t *flagp" "int excepts" +.Ft int +.Fn feraiseexcept "int excepts" +.Ft int +.Fn fesetexceptflag "const fexcept_t *flagp" "int excepts" +.Ft int +.Fn fetestexcept "int excepts" +.Sh DESCRIPTION +The +.Fn feclearexcept +routine clears the floating-point exception flags specified by +.Fa excepts , +whereas +.Fn feraiseexcept +raises the specified exceptions. +Raising an exception causes the corresponding flag to be set, +and a +.Dv SIGFPE +is delivered to the process if the exception is unmasked. +.Pp +The +.Fn fetestexcept +function determines which flags are currently set, of those specified by +.Fa excepts . +.Pp +The +.Fn fegetexceptflag +function stores the state of the exception flags specified in +.Fa excepts +in the opaque object pointed to by +.Fa flagp . +Similarly, +.Fn fesetexceptflag +changes the specified exception flags to reflect the state stored in +the object pointed to by +.Fa flagp . +Note that the flags restored with +.Fn fesetexceptflag +must be a (not necessarily proper) subset of the flags recorded by +a prior call to +.Fn fegetexceptflag . +.Pp +For all of these functions, the possible types of exceptions +include those described in +.Xr fenv 3 . +Some architectures may define other types of floating-point exceptions. +.Sh IMPLEMENTATION NOTES +On some architectures, raising an overflow or underflow exception +also causes an inexact exception to be raised. +In these cases, the overflow or underflow will be raised first. +.Pp +The +.Fn fegetexceptflag +and +.Fn fesetexceptflag +routines are preferred to +.Fn fetestexcept +and +.Fn feraiseexcept , +respectively, for saving and restoring exception flags. +The latter do not re-raise exceptions and may preserve +architecture-specific information such as addresses where +exceptions occurred. +.Sh RETURN VALUES +The +.Fn feclearexcept , +.Fn fegetexceptflag , +.Fn feraiseexcept , +and +.Fn fesetexceptflag +functions return 0 upon success, and non-zero otherwise. +The +.Fn fetestexcept +function returns the bitwise OR of the values of the current exception +flags that were requested. +.Sh SEE ALSO +.Xr sigaction 2 , +.Xr feholdexcept 3 , +.Xr fenv 3 , +.Xr feupdateenv 3 , +.Xr fpgetsticky 3 , +.Xr fpresetsticky 3 +.Sh STANDARDS +The +.Fn feclearexcept , +.Fn fegetexceptflag , +.Fn feraiseexcept , +.Fn fesetexceptflag , +and +.Fn fetestexcept +routines conform to +.St -isoC-99 . +.Sh HISTORY +These functions first appeared in +.Fx 5.3 . |