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ILOGB(3)	       FreeBSD Library Functions Manual		      ILOGB(3)

NAME
     ilogb, ilogbf, ilogbl, logb, logbf, logbl -- extract exponent

LIBRARY
     Math Library (libm, -lm)

SYNOPSIS
     #include <math.h>

     int
     ilogb(double x);

     int
     ilogbf(float x);

     int
     ilogbl(long double	x);

     double
     logb(double x);

     float
     logbf(float x);

     long double
     logbl(long	double x);

DESCRIPTION
     ilogb(), ilogbf() and ilogbl() return x's exponent	in integer format.
     ilogb(+-infinity) returns INT_MAX,	ilogb(+-NaN) returns FP_ILOGBNAN, and
     ilogb(0) returns FP_ILOGB0.

     logb(x), logbf(x),	and logbl(x) return x's	exponent in floating-point
     format with the same precision as x.  logb(+-infinity) returns +infinity,
     and logb(0) returns -infinity with	a division by zero exception.

SEE ALSO
     frexp(3), ieee(3),	math(3), scalbn(3)

STANDARDS
     The ilogb(), ilogbf(), ilogbl(), logb(), logbf(), and logbl() routines
     conform to	ISO/IEC	9899:1999 (``ISO C99'').  The latter three implement
     the logb function recommended by IEEE Std 754-1985.

HISTORY
     Function	First Appeared In
     logb()	4.3BSD
     ilogb()	FreeBSD	1.1.5
     ilogbf()	FreeBSD	2.0
     logbf()	FreeBSD	2.0
     ilogbl()	FreeBSD	5.4
     logbl()	FreeBSD	8.0

FreeBSD	Ports 11.2	       December	16, 2007	    FreeBSD Ports 11.2

NAME | LIBRARY | SYNOPSIS | DESCRIPTION | SEE ALSO | STANDARDS | HISTORY

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