## Linux and UNIX Man Pages

Test Your Knowledge in Computers #31
Difficulty: Easy
Alan Turing was the founder of IBM.
True or False?

# floorf(3) [freebsd man page]

```FLOOR(3)						   BSD Library Functions Manual 						  FLOOR(3)

NAME
floor, floorf, floorl -- largest integral value less than or equal to x

LIBRARY
Math Library (libm, -lm)

SYNOPSIS
#include <math.h>

double
floor(double x);

float
floorf(float x);

long double
floorl(long double x);

DESCRIPTION
The floor(), floorf() and floorl() functions return the largest integral value less than or equal to x, expressed as a floating-point number.

abs(3), ceil(3), fabs(3), ieee(3), math(3), rint(3), round(3), trunc(3)

STANDARDS
The floor() function conforms to ISO/IEC 9899:1990 (``ISO C90'').	The floorf() and floorl() functions conform to ISO/IEC 9899:1999
(``ISO C99'').

BSD								 January 13, 2005							       BSD```

## Check Out this Related Man Page

```FLOOR(3)						     Linux Programmer's Manual							  FLOOR(3)

NAME
floor, floorf, floorl - largest integral value not greater than argument

SYNOPSIS
#include <math.h>

double floor(double x);
float floorf(float x);
long double floorl(long double x);

DESCRIPTION
These functions round x down to the nearest integer.

RETURN VALUE
The rounded integer value. If x is integral or infinite, x itself is returned.

ERRORS
No errors other than EDOM and ERANGE can occur.	If x is NaN, then NaN is returned and errno may be set to EDOM.

NOTES
SUSv2  and POSIX 1003.1-2001 contain text about overflow (which might set errno to ERANGE, or raise an exception).  In practice, the result
cannot overflow on any current machine, so this error-handling stuff is just nonsense.  (More precisely, overflow can happen only when  the
maximum value of the exponent is smaller than the number of mantissa bits.  For the IEEE-754 standard 32-bit and 64-bit floating point num-
bers the maximum value of the exponent is 128 (resp. 1024), and the number of mantissa bits is 24 (resp. 53).)

CONFORMING TO
The floor() function conforms to SVID 3, POSIX, BSD 4.3, ISO 9899.  The other functions are from C99.