Texas Instruments TMS320C2x, User Manual

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Header Files
7-9 Run-Time-Support Functions
7.2.6 Floating-Point Math (math.h)
The math.h header defines several trigonometric, exponential, and hyperbolic
math functions. These functions are listed in Table 7
− 3 (d) on page 7-16. The
math functions expect double-precision floating-point arguments and return
double-precision floating-point values. Except where all trigonometic func-
tions use angles expressed as radians.
The math.h header also defines one macro named HUGE_VAL. The math
functions use this macro to represent out-of-range values. When a function
produces a floating-point return value that is too large to be represented, it
returns HUGE_VAL instead.
For all math.h functions, domain and range errors are handled by setting errno
to EDOM or ERANGE, as appropriate. The function input/outputs are rounded
to the nearest legal value.
7.2.7 Nonlocal Jumps (setjmp.h)
The setjmp.h header defines a type and a macro and declares a function for
bypassing the normal function call and return discipline. These include:
-
jmpbuf , an array type suitable for holding the information needed to
restore a calling environment
-
setjmp , a macro that saves its calling environment in its jmp_buf argument
for later use by the longjmp function
-
longjmp , a function that uses its jmp_buf argument to restore the program
environment
The nonlocal jump macro and function are listed in Table 7 − 3 (e) on page 7-17.
7.2.8 Variable Arguments (stdarg.h)
Some functions can have a variable number of arguments whose types can
differ. Such functions are called
variable-argument functions . The stdarg.h
header declares macros and a type that help you to use variable-argument
functions:
-
The macros are va_start , va_arg , and va_end . These macros are used
when the number and type of arguments may vary each time a function
is called.
-
The type va_list is a pointer type that can hold information for va_start,
va_end, and va_arg.