FEHOLDEXCEPT(3P)

PROLOG
This manual page is part of the POSIX Programmer's Manual. The Linux implementation of this interface may differ (consult the corresponding Linux manual page for details of Linux behavior), or the interface may not be implemented on Linux.

NAME
feholdexcept — save current floating-point environment

SYNOPSIS

#include <fenv.h>

int feholdexcept(fenv_t *envp);

DESCRIPTION
The functionality described on this reference page is aligned with the ISO C standard. Any conflict between the requirements described here and the ISO C standard is unintentional. This volume of POSIX.1-2017 defers to the ISO C standard.

The feholdexcept() function shall save the current floating-point environment in the object pointed to by envp, clear the floating-point status flags, and then install a non-stop (continue on floating-point exceptions) mode, if available, for all floating-point exceptions.

RETURN VALUE
The feholdexcept() function shall return zero if and only if non-stop floating-point exception handling was successfully installed.

ERRORS
No errors are defined.

The following sections are informative.

EXAMPLES
None.

APPLICATION USAGE
None.

RATIONALE
The feholdexcept() function should be effective on typical IEC 60559:1989 standard implementations which have the default non-stop mode and at least one other mode for trap handling or aborting. If the implementation provides only the non-stop mode, then installing the non-stop mode is trivial.

FUTURE DIRECTIONS
None.

SEE ALSO
fegetenv(), feupdateenv()

The Base Definitions volume of POSIX.1-2017, <fenv.h>

COPYRIGHT
Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1-2017, Standard for Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 7, 2018 Edition, Copyright (C) 2018 by the Institute of Electrical and Electronics Engineers, Inc and The Open Group. In the event of any discrepancy between this version and the original IEEE and The Open Group Standard, the original IEEE and The Open Group Standard is the referee document. The original Standard can be obtained online at http://www.opengroup.org/unix/online.html .

Any typographical or formatting errors that appear in this page are most likely to have been introduced during the conversion of the source files to man page format. To report such errors, see https://www.kernel.org/doc/man-pages/reporting_bugs.html .