man3/remquo.3

   1 .\" Copyright 2002 Walter Harms (walter.harms@informatik.uni-oldenburg.de)
   2 .\" and Copyright 2008, Linux Foundation, written by Michael Kerrisk
   3 .\"     <mtk.manpages@gmail.com>
   4 .\"
   5 .\" %%%LICENSE_START(GPL_NOVERSION_ONELINE)
   6 .\" Distributed under GPL
   7 .\" %%%LICENSE_END
   8 .\"
   9 .\" based on glibc infopages
  10 .\" polished, aeb
  11 .\"
  12 .TH REMQUO 3 2017-09-15 "GNU" "Linux Programmer's Manual"
  13 .SH NAME
  14 remquo, remquof, remquol \- remainder and part of quotient
  15 .SH SYNOPSIS
  16 .nf
  17 .B #include <math.h>
  18 .PP
  19 .BI "double remquo(double " x ", double " y ", int *" quo );
  20 .BI "float remquof(float " x ", float " y ", int *" quo );
  21 .BI "long double remquol(long double " x ", long double " y ", int *" quo );
  22 .fi
  23 .PP
  24 Link with \fI\-lm\fP.
  25 .PP
  26 .in -4n
  27 Feature Test Macro Requirements for glibc (see
  28 .BR feature_test_macros (7)):
  29 .in
  30 .PP
  31 .ad l
  32 .BR remquo (),
  33 .BR remquof (),
  34 .BR remquol ():
  35 .RS 4
  36 _ISOC99_SOURCE || _POSIX_C_SOURCE\ >=\ 200112L
  37 .RE
  38 .ad
  39 .SH DESCRIPTION
  40 These functions compute the remainder and part of the quotient
  41 upon division of
  42 .I x
  43 by
  44 .IR y .
  45 A few bits of the quotient are stored via the
  46 .I quo
  47 pointer.
  48 The remainder is returned as the function result.
  49 .PP
  50 The value of the remainder is the same as that computed by the
  51 .BR remainder (3)
  52 function.
  53 .PP
  54 The value stored via the
  55 .I quo
  56 pointer has the sign of
  57 .IR "x\ /\ y"
  58 and agrees with the quotient in at least the low order 3 bits.
  59 .PP
  60 For example, \fIremquo(29.0,\ 3.0)\fP returns \-1.0 and might store 2.
  61 Note that the actual quotient might not fit in an integer.
  62 .\" A possible application of this function might be the computation
  63 .\" of sin(x). Compute remquo(x, pi/2, &quo) or so.
  64 .\"
  65 .\" glibc, UnixWare: return 3 bits
  66 .\" MacOS 10: return 7 bits
  67 .SH RETURN VALUE
  68 On success, these functions return the same value as
  69 the analogous functions described in
  70 .BR remainder (3).
  71 .PP
  72 If
  73 .I x
  74 or
  75 .I y
  76 is a NaN, a NaN is returned.
  77 .PP
  78 If
  79 .I x
  80 is an infinity,
  81 and
  82 .I y
  83 is not a NaN,
  84 a domain error occurs, and
  85 a NaN is returned.
  86 .PP
  87 If
  88 .I y
  89 is zero,
  90 and
  91 .I x
  92 is not a NaN,
  93 a domain error occurs, and
  94 a NaN is returned.
  95 .SH ERRORS
  96 See
  97 .BR math_error (7)
  98 for information on how to determine whether an error has occurred
  99 when calling these functions.
 100 .PP
 101 The following errors can occur:
 102 .TP
 103 Domain error: \fIx\fP is an infinity or \fIy\fP is 0, \
 104 and the other argument is not a NaN
 105 .\" .I errno
 106 .\" is set to
 107 .\" .BR EDOM .
 108 An invalid floating-point exception
 109 .RB ( FE_INVALID )
 110 is raised.
 111 .PP
 112 These functions do not set
 113 .IR errno .
 114 .\" FIXME . Is it intentional that these functions do not set errno?
 115 .\" Bug raised: http://sources.redhat.com/bugzilla/show_bug.cgi?id=6802
 116 .SH VERSIONS
 117 These functions first appeared in glibc in version 2.1.
 118 .SH ATTRIBUTES
 119 For an explanation of the terms used in this section, see
 120 .BR attributes (7).
 121 .TS
 122 allbox;
 123 lbw30 lb lb
 124 l l l.
 125 Interface       Attribute       Value
 126 T{
 127 .BR remquo (),
 128 .BR remquof (),
 129 .BR remquol ()
 130 T}      Thread safety   MT-Safe
 131 .TE
 132 .SH CONFORMING TO
 133 C99, POSIX.1-2001, POSIX.1-2008.
 134 .SH SEE ALSO
 135 .BR fmod (3),
 136 .BR logb (3),
 137 .BR remainder (3)