man3/div.3

   1 .\" Copyright 1993 David Metcalfe (david@prism.demon.co.uk)
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  25 .\" References consulted:
  26 .\"     Linux libc source code
  27 .\"     Lewine's _POSIX Programmer's Guide_ (O'Reilly & Associates, 1991)
  28 .\"     386BSD man pages
  29 .\"
  30 .\" Modified 1993-03-29, David Metcalfe
  31 .\" Modified 1993-07-24, Rik Faith (faith@cs.unc.edu)
  32 .\" Modified 2002-08-10, 2003-11-01 Walter Harms, aeb
  33 .\"
  34 .TH DIV 3 2016-03-15 "" "Linux Programmer's Manual"
  35 .SH NAME
  36 div, ldiv, lldiv, imaxdiv \- compute quotient and remainder of
  37 an integer division
  38 .SH SYNOPSIS
  39 .nf
  40 .B #include <stdlib.h>
  41 .PP
  42 .BI "div_t div(int " numerator ", int " denominator );
  43 .BI "ldiv_t ldiv(long " numerator ", long " denominator );
  44 .BI "lldiv_t lldiv(long long " numerator ", long long " denominator );
  45 .PP
  46 .B #include <inttypes.h>
  47 .PP
  48 .BI "imaxdiv_t imaxdiv(intmax_t " numerator ", intmax_t " denominator );
  49 .fi
  50 .PP
  51 .in -4n
  52 Feature Test Macro Requirements for glibc (see
  53 .BR feature_test_macros (7)):
  54 .in
  55 .ad l
  56 .PP
  57 .BR lldiv ():
  58 .RS 4
  59 _ISOC99_SOURCE || _POSIX_C_SOURCE\ >=\ 200112L
  60 .RE
  61 .ad
  62 .SH DESCRIPTION
  63 The
  64 .BR div ()
  65 function computes the value
  66 \fInumerator\fP/\fIdenominator\fP and
  67 returns the quotient and remainder in a structure
  68 named \fIdiv_t\fP that contains
  69 two integer members (in unspecified order) named \fIquot\fP and \fIrem\fP.
  70 The quotient is rounded toward zero.
  71 The result satisfies \fIquot\fP*\fIdenominator\fP+\fIrem\fP = \fInumerator\fP.
  72 .PP
  73 The
  74 .BR ldiv (),
  75 .BR lldiv (),
  76 and
  77 .BR imaxdiv ()
  78 functions do the same,
  79 dividing numbers of the indicated type and
  80 returning the result in a structure
  81 of the indicated name, in all cases with fields \fIquot\fP and \fIrem\fP
  82 of the same type as the function arguments.
  83 .SH RETURN VALUE
  84 The \fIdiv_t\fP (etc.) structure.
  85 .SH ATTRIBUTES
  86 For an explanation of the terms used in this section, see
  87 .BR attributes (7).
  88 .TS
  89 allbox;
  90 lbw33 lb lb
  91 l l l.
  92 Interface       Attribute       Value
  93 T{
  94 .BR div (),
  95 .BR ldiv (),
  96 .BR lldiv (),
  97 .BR imaxdiv ()
  98 T}      Thread safety   MT-Safe
  99 .TE
 100 .SH CONFORMING TO
 101 POSIX.1-2001, POSIX.1-2008, C89, C99, SVr4, 4.3BSD.
 102 The functions
 103 .BR lldiv ()
 104 and
 105 .BR imaxdiv ()
 106 were added in C99.
 107 .SH EXAMPLE
 108 After
 109 .PP
 110 .in +4n
 111 .EX
 112 div_t q = div(\-5, 3);
 113 .EE
 114 .in
 115 .PP
 116 the values \fIq.quot\fP and \fIq.rem\fP are \-1 and \-2, respectively.
 117 .SH SEE ALSO
 118 .BR abs (3),
 119 .BR remainder (3)