NAME
ceil() — ceiling function
SYNOPSIS
#include <math.h>
double ceil(double x);
DESCRIPTION
ceil()
returns the smallest integer (represented as a double-precision number)
not less than
x.
To use this function, make sure your program includes
<math.h>,
and link in the math library by specifying
-lm
on the compiler or linker command line.
RETURN VALUE
If
x
is
±INFINITY or ±zero,
ceil()
returns
x.
If
x
is NaN,
ceil()
returns NaN.
If the correct value would overflow,
ceil()
returns
HUGE_VAL
and sets
errno
to [ERANGE]. (This description complies with XPG4.2; however, the
ceil()
function never overflows on HP-UX systems.)
ERRORS
If
ceil()
fails,
errno
is set to the following value.
- [ERANGE]
The correct value would overflow.
STANDARDS CONFORMANCE
ceil(): SVID3, XPG4.2, ANSI C
