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fltenv.h
Prototype
int feclearexcept(int excepts);
Description
Clears the exceptions specified by excepts. The following exception flags expand to integer values that are a power of 2.
Flag/Meaning
Return Value
Returns a non-zero value if all the exceptions specified by excepts are valid; otherwise, the return value is 0.
Compatibility
DOS Windows 3.x Phar Lap DOSX Win32
See Also
fltenv.h
Prototype
void fegetenv(fenv_t * envp);
Description
Copies the current floating-point environment (rounding mode, precision mode, and exceptions) into the buffer pointed to by envp. Type fenv_t represents the state of the complete floating-point environment. Macro FE_DFL_ENV, which represents the default floating-point environment, expands to a value with type fenv_t. To use this function and the other functions defined in fltenv.h, your compiler must support the extensions to C as specified by the Numerical C Extensions Group (NCEG). The NCEG includes two predefined macros that determine if a compiler supports the extensions:
__FPCE__
When defined, indicates a compiler's compliance with the NCEG document. This macro is defined by the compiler as a constant value of 1.
__FPCE_IEEE__
When defined, indicates the compiler is compliant with the IEEE portion of the NCEG document. This macro is defined by the compiler as a constant value of 1.
Return Value
None
Compatibility
DOS Windows 3.x Phar Lap DOSX Win32
See Also
fltenv.h
Prototype
int fegetexcept(fexcept_t *flagp, int excepts);
Description
Stores (in the structure pointed to by flagp) an implementation-specific
representation of the exception flag specified by excepts.
Type fexcept_t represents an exception flag. The following
exception flags expand to an integer value that is a power of 2.
Flag/Meaning
Return Value
Returns a non-zero value if the exception specified by excepts is valid; otherwise, the return value is 0.
Compatibility
DOS Windows 3.x Phar Lap DOSX Win32
See Also
fegetenv for predefined macros in support of NCEG extensions.
fltenv.h
Prototype
int fegetprec(void);
Description
Gets the current precision mode.
Return Value
The current precision mode.
Compatibility
DOS Windows 3.x Phar Lap DOSX Win32
See Also
fegetenv for predefined macros in support of NCEG extensions.
fltenv.h
Prototype
int fegetround(void);
Description
Gets the current rounding mode. The following rounding modes each expand to a unique, positive constant of type int:
Return Value
One of the rounding constants defined above.
Compatibility
DOS Windows 3.x Phar Lap DOSX Win32
See Also
fegetenv for predefined macros in support of NCEG extensions.
fltenv.h
Prototype
void feprocentry(fenv_t * envp);
Description
Copies the current floating-point environment (rounding mode, precision mode, and exceptions) into the buffer pointed to by envp, and resets the floating-point environment to the start-up state (round to nearest, no loss in precision, and no exceptions set). Type fenv_t represents the state of the complete floating-point environment. Macro FE_DFL_ENV, which represents the default floating-point environment, expands to a value with type fenv_t.
Return Value
None
Compatibility
DOS Windows 3.x Phar Lap DOSX Win32
See Also
fegetenv for predefined marcros in support of NCEG extensions.
fltenv.h
Prototype
void feprocexit(const fenv_t * envp);
Description
Saves the current exceptions internally, sets the floating-point environment to the values stored in the buffer pointed to by envp, and then raises the saved exceptions. Type fenv_t represents the state of the complete floating-point environment. Macro FE_DFL_ENV, which represents the default floating-point environment, expands to a value of type fenv_t.
Return Value
None
Compatibility
DOS Windows 3.x Phar Lap DOSX Win32
See Also
fegetenv for predefined macros in support of NCEG extensions.
fltenv.h
Prototype
int feraiseexcept(int excepts);
Description
Raises the exceptions specified by excepts.
Return Value
Returns a non-zero value if all exceptions specified by excepts are valid; otherwise, the return value is 0. The following exception flags expand to integer values that are a power of 2.
Compatibility
DOS Windows 3.x Phar Lap DOSX Win32
See Also
feclearexcept
fegetenv for predefined macros in support of NCEG extensions.
fltenv.h
Prototype
void fesetenv(const fenv_t *envp);
Description
Sets the current floating-point environment (rounding mode, precision mode, and exceptions) to the values stored in the buffer pointed to by envp. Type fenv_t represents the state of the complete floating-point environment. Macro FE_DFL_ENV, which represents the default floating-point environment, expands to a value with type fenv_t.
Return Value
None
Compatibility
DOS Windows 3.x Phar Lap DOSX Win32
See Also
fegetenv for predefined macros in support of NCEG extensions.
fltenv.h
Prototype
int fesetexcept(const fexcept_t *flagp, int excepts);
Description
Sets the implementation-specific exception flag (from the structure pointed to by flagp) of the exception flag specified by excepts. flagp should have been set by a previous call to fegetexcept; if not, the results are unpredictable. Type fexcept_t represents an exception flag. The following exception flags expand to integer values that are a power of 2.
Return Value
Returns non-zero if the exception specified by excepts is valid; Otherwise, the return value is 0.
Compatibility
DOS Windows 3.x Phar Lap DOSX Win32
See Also
fegetexcept
fegetenv for predefined macros in support of NCEG extensions.
fltenv.h
Prototype
int fesetprec(int prec);
Description
Sets the precision mode to the value specified by prec. Precision mode has meaning only when inline coprocessor instructions are used; there is no affect without a coprocessor. The following precision modes each expands to a unique constant of type int. When the program begins, precision mode is FE_LDBLPREC.
Return Value
If prec is not one of the values specified in section 17. 2. 7, fesetprec returns 0. Otherwise, it returns a non-zero value.
Compatibility
DOS Windows 3.x Phar Lap DOSX Win32
See Also
fegetprec
fegetenv for predefined macros in support of NCEG extensions.
fltenv.h
Prototype
int fesetround(int round);
Description
Sets the rounding mode. The previous rounding mode is forgotten. The following rounding modes each expands to a unique, positive constant of type int:
Return Value
Non-zero if successful; zero if invalid value given for round.
Compatibility
DOS Windows 3.x Phar Lap DOSX Win32
See Also
fegetround
fegetenv for predefined macros in support of NCEG extensions.
fltenv.h
Prototype
int fetestexcept(int excepts);
Description
This function determines if any of the exceptions specified by excepts have been raised. The following exception flags expand to integer values that are a power of 2.
Return Value
The bitwise OR of the exceptions corresponding to the currently-raised exceptions specified by excepts. If none of the specified exceptions is raised, the return value is zero.
Compatibility
DOS Windows 3.x Phar Lap DOSX Win32
See Also
fegetenv for predefined macros in support of NCEG extensions.