.\"
.\" Copyright (c) 2026 Faraz Vahedi <kfv@FreeBSD.org>
.\"
.\" SPDX-License-Identifier: BSD-2-Clause
.\"
.Dd August 31, 2026
.Dt FEGETMODE 3
.Os
.Sh NAME
.Nm fegetmode ,
.Nm fesetmode
.Nd save and restore floating-point control modes
.Sh LIBRARY
.Lb libm
.Sh SYNOPSIS
.In fenv.h
.Fd "#pragma STDC FENV_ACCESS ON"
.Ft int
.Fn fegetmode "femode_t *modep"
.Ft int
.Fn fesetmode "const femode_t *modep"
.Sh DESCRIPTION
The
.Vt femode_t
type represents the dynamic floating-point control modes,
including the rounding direction and, where supported, exception
masks and other implementation-defined modes.
.Pp
The
.Fn fegetmode
function stores the current control modes in the object
pointed to by
.Fa modep .
.Pp
The
.Fn fesetmode
function establishes the control modes represented by
.Fa modep .
The argument
.Fa modep
must point to an object set by a prior call to
.Fn fegetmode ,
or equal
.Dv FE_DFL_MODE .
.Dv FE_DFL_MODE
expands to a pointer to the default control modes
.Po
installed at program startup
.Pc .
.Sh RETURN VALUES
The
.Fn fegetmode
and
.Fn fesetmode
functions return 0 if they succeed, and non-zero otherwise;
however, the present implementation always succeeds.
.Sh SEE ALSO
.Xr fenv 3 ,
.Xr fegetround 3 ,
.Xr fesetround 3
.Sh STANDARDS
The
.Fn fegetmode
and
.Fn fesetmode
functions conform to
.St -isoC-2023 .
.Sh HISTORY
These routines first appeared in
.Fx 16.0 .