sqrt(2)

NAME
     _sqrt_s, _sqrt_d - single and double precision sqrt function.

SYNOPSIS
     #include <unistd.h>
     float _sqrt_s (float v)
     double _sqrt_d (double v)

DESCRIPTION
     These single/double precision routines listed above are available in
     libc.  These should not be confused with the standard math library square
     root functions [see sqrt (3M)].

     If v is a negative, the sqrt functions will return a NaN, but won't set
     the errno value.  This is done since the ABI doesn't specify a errno
     value if the v is negative.

SEE ALSO
     sqrt(3M), errno(3C)