1REMQUO(3P)                 POSIX Programmer's Manual                REMQUO(3P)
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PROLOG

6       This  manual  page is part of the POSIX Programmer's Manual.  The Linux
7       implementation of this interface may differ (consult the  corresponding
8       Linux  manual page for details of Linux behavior), or the interface may
9       not be implemented on Linux.
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11

NAME

13       remquo, remquof, remquol — remainder functions
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SYNOPSIS

16       #include <math.h>
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18       double remquo(double x, double y, int *quo);
19       float remquof(float x, float y, int *quo);
20       long double remquol(long double x, long double y, int *quo);
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DESCRIPTION

23       The functionality described on this reference page is aligned with  the
24       ISO C  standard.  Any  conflict between the requirements described here
25       and the ISO C standard is unintentional. This  volume  of  POSIX.1‐2008
26       defers to the ISO C standard.
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28       The remquo(), remquof(), and remquol() functions shall compute the same
29       remainder as the remainder(), remainderf(), and remainderl() functions,
30       respectively. In the object pointed to by quo, they store a value whose
31       sign is the sign of x/y and whose magnitude is congruent modulo  2n  to
32       the  magnitude of the integral quotient of x/y, where n is an implemen‐
33       tation-defined integer greater than or equal to 3. If y  is  zero,  the
34       value stored in the object pointed to by quo is unspecified.
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36       An  application  wishing to check for error situations should set errno
37       to zero and  call  feclearexcept(FE_ALL_EXCEPT)  before  calling  these
38       functions. On return, if errno is non-zero or fetestexcept(FE_INVALID |
39       FE_DIVBYZERO | FE_OVERFLOW | FE_UNDERFLOW) is non-zero,  an  error  has
40       occurred.
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RETURN VALUE

43       These functions shall return x REM y.
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45       On  systems that do not support the IEC 60559 Floating-Point option, if
46       y is zero, it is implementation-defined whether a domain  error  occurs
47       or zero is returned.
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49       If x or y is NaN, a NaN shall be returned.
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51       If  x  is ±Inf or y is zero and the other argument is non-NaN, a domain
52       error shall occur, and a NaN shall be returned.
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ERRORS

55       These functions shall fail if:
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57       Domain Error
58                   The x argument is ±Inf, or the y argument  is  ±0  and  the
59                   other argument is non-NaN.
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61                   If  the  integer expression (math_errhandling & MATH_ERRNO)
62                   is non-zero, then errno shall be set  to  [EDOM].   If  the
63                   integer  expression  (math_errhandling & MATH_ERREXCEPT) is
64                   non-zero, then the invalid floating-point  exception  shall
65                   be raised.
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67       These functions may fail if:
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69       Domain Error
70                   The y argument is zero.
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72                   If  the  integer expression (math_errhandling & MATH_ERRNO)
73                   is non-zero, then errno shall be set  to  [EDOM].   If  the
74                   integer  expression  (math_errhandling & MATH_ERREXCEPT) is
75                   non-zero, then the invalid floating-point  exception  shall
76                   be raised.
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78       The following sections are informative.
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EXAMPLES

81       None.
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APPLICATION USAGE

84       On   error,   the   expressions  (math_errhandling  &  MATH_ERRNO)  and
85       (math_errhandling & MATH_ERREXCEPT) are independent of each other,  but
86       at least one of them must be non-zero.
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RATIONALE

89       These functions are intended for implementing argument reductions which
90       can exploit a few low-order bits of the quotient. Note that x may be so
91       large  in  magnitude  relative to y that an exact representation of the
92       quotient is not practical.
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FUTURE DIRECTIONS

95       None.
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SEE ALSO

98       feclearexcept(), fetestexcept(), remainder()
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100       The Base Definitions volume of POSIX.1‐2008, Section 4.19, Treatment of
101       Error Conditions for Mathematical Functions, <math.h>
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104       Portions  of  this text are reprinted and reproduced in electronic form
105       from IEEE Std 1003.1, 2013 Edition, Standard for Information Technology
106       --  Portable  Operating  System  Interface (POSIX), The Open Group Base
107       Specifications Issue 7, Copyright (C) 2013 by the Institute of Electri‐
108       cal  and  Electronics  Engineers,  Inc  and  The  Open Group.  (This is
109       POSIX.1-2008 with the 2013 Technical Corrigendum  1  applied.)  In  the
110       event of any discrepancy between this version and the original IEEE and
111       The Open Group Standard, the original IEEE and The Open Group  Standard
112       is  the  referee document. The original Standard can be obtained online
113       at http://www.unix.org/online.html .
114
115       Any typographical or formatting errors that appear  in  this  page  are
116       most likely to have been introduced during the conversion of the source
117       files to man page format. To report such errors,  see  https://www.ker
118       nel.org/doc/man-pages/reporting_bugs.html .
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122IEEE/The Open Group                  2013                           REMQUO(3P)
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