ref: 626eb6de0f82e40f432e7b22a02a1040202d03d5
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.