.TH LIBJ2_CO_J2U 3 LIBJ2 .SH NAME libj2_co_j2u \- Count ones .SH SYNOPSIS .nf #include unsigned \fBlibj2_co_j2u\fP(const struct libj2_j2u *\fIa\fP); .fi .PP Link with .IR -lj2 . .SH DESCRIPTION The .BR libj2_co_j2u () function returns the number of set bits in .IR a . .PP .I a is assumed to be .RI non- NULL . .SH RETURN VALUE The .BR libj2_co_j2u () function returns the number of set bits in .IR a . .SH ERRORS The .BR libj2_co_j2u () function cannot fail. .SH HISTORY The .BR libj2_co_j2u () function was added in version 1.0 of .BR libj2 . .SH SEE ALSO .BR libj2 (7), .BR libj2_cz_j2u (3), .BR libj2_parity_j2u (3), .BR libj2_clo_j2u (3), .BR libj2_cto_j2u (3)