4.4BSD/usr/share/man/cat3/rint.0

RINT(3)                     BSD Programmer's Manual                    RINT(3)

NNAAMMEE
     rriinntt - and round-to-closest integer functions

SSYYNNOOPPSSIISS
     ##iinncclluuddee <<mmaatthh..hh>>

     _d_o_u_b_l_e
     rriinntt(_d_o_u_b_l_e _x);

DDEESSCCRRIIPPTTIIOONN
     The rriinntt() function finds the integer (represented as a double precision
     number) nearest to _x in the direction of the prevailing rounding mode.

NNOOTTEESS
     On a VAX, rriinntt(_x) is equivalent to adding half to the magnitude and then
     rounding towards zero.

     In the default rounding mode, to nearest, on a machine that conforms to
     IEEE 754, rriinntt(_x) is the integer nearest _x with the additional stipula-
     tion that if |rint(x)-x|=1/2 then rriinntt(_x) is even.  Other rounding modes
     can make rriinntt() act like fflloooorr(), or like cceeiill(), or round towards zero.

     Another way to obtain an integer near _x is to declare (in C)

           double x;     int k;    k = x;

     Most C compilers round _x towards 0 to get the integer _k, but some do oth-
     erwise.  If in doubt, use fflloooorr(), cceeiill(), or rriinntt() first, whichever you
     intend.  Also note that, if x is larger than _k can accommodate, the value
     of _k and the presence or absence of an integer overflow are hard to pre-
     dict.

SSEEEE AALLSSOO
     abs(3),  fabs(3),  ceil(3),  floor(3),  ieee(3),  math(3)

HHIISSTTOORRYY
     A rriinntt() function appeared in Version 6 AT&T UNIX.

4.4BSD                           June 4, 1993                                1