man3/div.3

   1 .\" Copyright 1993 David Metcalfe (david@prism.demon.co.uk)
   2 .\"
   3 .\" SPDX-License-Identifier: Linux-man-pages-copyleft
   4 .\"
   5 .\" References consulted:
   6 .\"     Linux libc source code
   7 .\"     Lewine's _POSIX Programmer's Guide_ (O'Reilly & Associates, 1991)
   8 .\"     386BSD man pages
   9 .\"
  10 .\" Modified 1993-03-29, David Metcalfe
  11 .\" Modified 1993-07-24, Rik Faith (faith@cs.unc.edu)
  12 .\" Modified 2002-08-10, 2003-11-01 Walter Harms, aeb
  13 .\"
  14 .TH DIV 3 2021-03-22 "" "Linux Programmer's Manual"
  15 .SH NAME
  16 div, ldiv, lldiv, imaxdiv \- compute quotient and remainder of
  17 an integer division
  18 .SH LIBRARY
  19 Standard C library
  20 .RI ( libc ", " \-lc )
  21 .SH SYNOPSIS
  22 .nf
  23 .B #include <stdlib.h>
  24 .PP
  25 .BI "div_t div(int " numerator ", int " denominator );
  26 .BI "ldiv_t ldiv(long " numerator ", long " denominator );
  27 .BI "lldiv_t lldiv(long long " numerator ", long long " denominator );
  28 .PP
  29 .B #include <inttypes.h>
  30 .PP
  31 .BI "imaxdiv_t imaxdiv(intmax_t " numerator ", intmax_t " denominator );
  32 .fi
  33 .PP
  34 .RS -4
  35 Feature Test Macro Requirements for glibc (see
  36 .BR feature_test_macros (7)):
  37 .RE
  38 .PP
  39 .BR lldiv ():
  40 .nf
  41     _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L
  42 .fi
  43 .SH DESCRIPTION
  44 The
  45 .BR div ()
  46 function computes the value
  47 \fInumerator\fP/\fIdenominator\fP and
  48 returns the quotient and remainder in a structure
  49 named \fIdiv_t\fP that contains
  50 two integer members (in unspecified order) named \fIquot\fP and \fIrem\fP.
  51 The quotient is rounded toward zero.
  52 The result satisfies \fIquot\fP*\fIdenominator\fP+\fIrem\fP = \fInumerator\fP.
  53 .PP
  54 The
  55 .BR ldiv (),
  56 .BR lldiv (),
  57 and
  58 .BR imaxdiv ()
  59 functions do the same,
  60 dividing numbers of the indicated type and
  61 returning the result in a structure
  62 of the indicated name, in all cases with fields \fIquot\fP and \fIrem\fP
  63 of the same type as the function arguments.
  64 .SH RETURN VALUE
  65 The \fIdiv_t\fP (etc.) structure.
  66 .SH ATTRIBUTES
  67 For an explanation of the terms used in this section, see
  68 .BR attributes (7).
  69 .ad l
  70 .nh
  71 .TS
  72 allbox;
  73 lbx lb lb
  74 l l l.
  75 Interface       Attribute       Value
  76 T{
  77 .BR div (),
  78 .BR ldiv (),
  79 .BR lldiv (),
  80 .BR imaxdiv ()
  81 T}      Thread safety   MT-Safe
  82 .TE
  83 .hy
  84 .ad
  85 .sp 1
  86 .SH CONFORMING TO
  87 POSIX.1-2001, POSIX.1-2008, C89, C99, SVr4, 4.3BSD.
  88 The functions
  89 .BR lldiv ()
  90 and
  91 .BR imaxdiv ()
  92 were added in C99.
  93 .SH EXAMPLES
  94 After
  95 .PP
  96 .in +4n
  97 .EX
  98 div_t q = div(\-5, 3);
  99 .EE
 100 .in
 101 .PP
 102 the values \fIq.quot\fP and \fIq.rem\fP are \-1 and \-2, respectively.
 103 .SH SEE ALSO
 104 .BR abs (3),
 105 .BR remainder (3)