ceil, ceilf, ceill - round up floating-point number

Syntax	#include <math.h> double ceil(double x); float ceilf(float x); long double ceill(long double x);
Description	These functions round up a floating-point number to an integer value.
Return val.	Lowest integer in floating point format which is greater than or equal to x.
Note	The integer value returned by ceil(), ceilf() and ceill() as double, float or long double cannot always be represented as int or long int. The result should always be checked before it is assigned to a variable of type int, so that an integer overflow can be caught. To make sure that any errors are caught, errno should be set to 0 before ceil(), ceilf() or ceill() is called. If after the execution errno != 0, an error has occurred.
See also	abs(), fabs(), floor(), floorf(), floorl(), isnan(), math.h.