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35 #if defined(LIBC_SCCS) && !defined(lint)
36 static char sccsid[] = "@(#)div.c 8.1 (Berkeley) 6/4/93";
37 #endif /* LIBC_SCCS and not lint */
38 #include <sys/cdefs.h>
39 __FBSDID("$FreeBSD$");
41 #include <stdlib.h> /* div_t */
44 div(int num, int denom)
50 #if !defined(__STDC_VERSION__) || (__STDC_VERSION__ < 199901L)
52 * The ANSI standard says that |r.quot| <= |n/d|, where
53 * n/d is to be computed in infinite precision. In other
54 * words, we should always truncate the quotient towards
57 * Machine division and remainer may work either way when
58 * one or both of n or d is negative. If only one is
59 * negative and r.quot has been truncated towards -inf,
60 * r.rem will have the same sign as denom and the opposite
61 * sign of num; if both are negative and r.quot has been
62 * truncated towards -inf, r.rem will be positive (will
63 * have the opposite sign of num). These are considered
66 * If both are num and denom are positive, r will always
69 * This all boils down to:
70 * if num >= 0, but r.rem < 0, we got the wrong answer.
71 * In that case, to get the right answer, add 1 to r.quot and
72 * subtract denom from r.rem.
74 if (num >= 0 && r.rem < 0) {