ref: da5c0bada7be9dd82ca1f63e621670143597d3bb
dir: /sys/man/2/muldiv/
.TH MULDIV 2 .SH NAME muldiv, umuldiv \- high-precision multiplication and division .SH SYNOPSIS .B #include <u.h> .br .B #include <libc.h> .PP .B long muldiv(long a, long b, long c) .PP .B ulong umuldiv(ulong a, ulong b, ulong c) .SH DESCRIPTION .I Muldiv returns .BR a*b/c , using a .B vlong to hold the intermediate result. .I Umuldiv is the equivalent for unsigned integers. They can be used to scale integer values without worry about overflowing the intermediate result. .PP On some architectures, these routines can generate a trap if the final result does not fit in a .B long or .BR ulong ; on others they will silently truncate.