Q_QADDI(3)             FreeBSD Library Functions Manual             Q_QADDI(3)

NAME
     Q_QADDI, Q_QDIVI, Q_QMULI, Q_QSUBI, Q_QFRACI, Q_QCPYVALI - fixed-point
     math functions which apply integers to a Q number

SYNOPSIS
     #include <sys/qmath.h>

     int
     Q_QADDI(QTYPE *a, ITYPE b);

     int
     Q_QDIVI(QTYPE *a, ITYPE b);

     int
     Q_QMULI(QTYPE *a, ITYPE b);

     int
     Q_QSUBI(QTYPE *a, ITYPE b);

     int
     Q_QFRACI(QTYPE *q, ITYPE n, ITYPE d);

     int
     Q_QCPYVALI(QTYPE *q, ITYPE i);

DESCRIPTION
     The Q_QADDI(), Q_QDIVI(), Q_QMULI() and Q_QSUBI() functions add, divide,
     multiply or subtract b to/by/from a respectively, storing the result in
     a.

     The Q_QFRACI() function computes the fraction n divided by d and stores
     the fixed-point result in q.

     The Q_QCPYVALI() function overwrites q's integer and fractional bits with
     the Q representation of integer value i.

     All of those functions operate on the following data types: s8q_t, u8q_t,
     s16q_t, u16q_t, s32q_t, u32q_t, s64q_t, and u64q_t, which are referred to
     generically as QTYPE.  The ITYPE refers to the stdint(7) integer types.

     For more details, see qmath(3).

RETURN VALUES
     Q_QADDI(), Q_QDIVI(), Q_QMULI(), Q_QSUBI(), Q_QFRACI() and Q_QCPYVALI()
     functions return 0 on success, or an errno on failure.  EINVAL is
     returned for divide-by-zero.  EOVERFLOW and ERANGE are returned for
     overflow and underflow respectively.

SEE ALSO
     errno(2), qmath(3), stdint(7)

HISTORY
     The qmath(3) functions first appeared in FreeBSD 13.0.

AUTHORS
     The qmath(3) functions and this manual page were written by Lawrence
     Stewart <lstewart@FreeBSD.org> and sponsored by Netflix, Inc.

FreeBSD 13.1-RELEASE-p6          July 8, 2018          FreeBSD 13.1-RELEASE-p6