man3/div.3

   1 '\" t
   2 .\" Copyright 1993 David Metcalfe (david@prism.demon.co.uk)
   3 .\"
   4 .\" SPDX-License-Identifier: Linux-man-pages-copyleft
   5 .\"
   6 .\" References consulted:
   7 .\"     Linux libc source code
   8 .\"     Lewine's _POSIX Programmer's Guide_ (O'Reilly & Associates, 1991)
   9 .\"     386BSD man pages
  10 .\"
  11 .\" Modified 1993-03-29, David Metcalfe
  12 .\" Modified 1993-07-24, Rik Faith (faith@cs.unc.edu)
  13 .\" Modified 2002-08-10, 2003-11-01 Walter Harms, aeb
  14 .\"
  15 .TH div 3 (date) "Linux man-pages (unreleased)"
  16 .SH NAME
  17 div, ldiv, lldiv, imaxdiv \- compute quotient and remainder of
  18 an integer division
  19 .SH LIBRARY
  20 Standard C library
  21 .RI ( libc ", " \-lc )
  22 .SH SYNOPSIS
  23 .nf
  24 .B #include <stdlib.h>
  25 .PP
  26 .BI "div_t div(int " numerator ", int " denominator );
  27 .BI "ldiv_t ldiv(long " numerator ", long " denominator );
  28 .BI "lldiv_t lldiv(long long " numerator ", long long " denominator );
  29 .PP
  30 .B #include <inttypes.h>
  31 .PP
  32 .BI "imaxdiv_t imaxdiv(intmax_t " numerator ", intmax_t " denominator );
  33 .fi
  34 .PP
  35 .RS -4
  36 Feature Test Macro Requirements for glibc (see
  37 .BR feature_test_macros (7)):
  38 .RE
  39 .PP
  40 .BR lldiv ():
  41 .nf
  42     _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L
  43 .fi
  44 .SH DESCRIPTION
  45 The
  46 .BR div ()
  47 function computes the value
  48 \fInumerator\fP/\fIdenominator\fP and
  49 returns the quotient and remainder in a structure
  50 named \fIdiv_t\fP that contains
  51 two integer members (in unspecified order) named \fIquot\fP and \fIrem\fP.
  52 The quotient is rounded toward zero.
  53 The result satisfies \fIquot\fP*\fIdenominator\fP+\fIrem\fP = \fInumerator\fP.
  54 .PP
  55 The
  56 .BR ldiv (),
  57 .BR lldiv (),
  58 and
  59 .BR imaxdiv ()
  60 functions do the same,
  61 dividing numbers of the indicated type and
  62 returning the result in a structure
  63 of the indicated name, in all cases with fields \fIquot\fP and \fIrem\fP
  64 of the same type as the function arguments.
  65 .SH RETURN VALUE
  66 The \fIdiv_t\fP (etc.) structure.
  67 .SH ATTRIBUTES
  68 For an explanation of the terms used in this section, see
  69 .BR attributes (7).
  70 .ad l
  71 .nh
  72 .TS
  73 allbox;
  74 lbx lb lb
  75 l l l.
  76 Interface       Attribute       Value
  77 T{
  78 .BR div (),
  79 .BR ldiv (),
  80 .BR lldiv (),
  81 .BR imaxdiv ()
  82 T}      Thread safety   MT-Safe
  83 .TE
  84 .hy
  85 .ad
  86 .sp 1
  87 .SH STANDARDS
  88 C11, POSIX.1-2008.
  89 .SH HISTORY
  90 POSIX.1-2001, C89, C99, SVr4, 4.3BSD.
  91 .PP
  92 .BR lldiv ()
  93 and
  94 .BR imaxdiv ()
  95 were added in C99.
  96 .SH EXAMPLES
  97 After
  98 .PP
  99 .in +4n
 100 .EX
 101 div_t q = div(\-5, 3);
 102 .EE
 103 .in
 104 .PP
 105 the values \fIq.quot\fP and \fIq.rem\fP are \-1 and \-2, respectively.
 106 .SH SEE ALSO
 107 .BR abs (3),
 108 .BR remainder (3)