fegetenv(3p) — Linux manual page

FEGETENV(3P)            POSIX Programmer's Manual            FEGETENV(3P)

PROLOG         top

       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         top

       fegetenv, fesetenv — get and set current floating-point
       environment

SYNOPSIS         top

       #include <fenv.h>

       int fegetenv(fenv_t *envp);
       int fesetenv(const fenv_t *envp);

DESCRIPTION         top

       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 fegetenv() function shall attempt to store the current
       floating-point environment in the object pointed to by envp.

       The fesetenv() function shall attempt to establish the floating-
       point environment represented by the object pointed to by envp.
       The argument envp shall point to an object set by a call to
       fegetenv() or feholdexcept(), or equal a floating-point
       environment macro. The fesetenv() function does not raise
       floating-point exceptions, but only installs the state of the
       floating-point status flags represented through its argument.

RETURN VALUE         top

       If the representation was successfully stored, fegetenv() shall
       return zero. Otherwise, it shall return a non-zero value.  If the
       environment was successfully established, fesetenv() shall return
       zero. Otherwise, it shall return a non-zero value.

ERRORS         top

       No errors are defined.

       The following sections are informative.

EXAMPLES         top

       None.

APPLICATION USAGE         top

       None.

RATIONALE         top

       None.

FUTURE DIRECTIONS         top

       None.

SEE ALSO         top

       feholdexcept(3p), feupdateenv(3p)

       The Base Definitions volume of POSIX.1‐2017, fenv.h(0p)

COPYRIGHT         top

       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 .

IEEE/The Open Group                2017                      FEGETENV(3P)

Pages that refer to this page: fenv.h(0p),  feholdexcept(3p),  fesetenv(3p),  feupdateenv(3p)

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