1LLRINT(3P) POSIX Programmer's Manual LLRINT(3P)
2
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.
10
13 llrint, llrintf, llrintl — round to the nearest integer value using
14 current rounding direction
15
17 #include <math.h>
18 long long llrint(double x);
20 long long llrintf(float x);
21 long long llrintl(long double x);
22
24 The functionality described on this reference page is aligned with the
25 ISO C standard. Any conflict between the requirements described here
26 and the ISO C standard is unintentional. This volume of POSIX.1‐2008
27 defers to the ISO C standard.
28 These functions shall round their argument to the nearest integer
30 value, rounding according to the current rounding direction.
31 An application wishing to check for error situations should set errno
33 to zero and call feclearexcept(FE_ALL_EXCEPT) before calling these
34 functions. On return, if errno is non-zero or fetestexcept(FE_INVALID |
35 FE_DIVBYZERO | FE_OVERFLOW | FE_UNDERFLOW) is non-zero, an error has
36 occurred.
37
39 Upon successful completion, these functions shall return the rounded
40 integer value.
41 If x is NaN, a domain error shall occur, and an unspecified value is
43 returned.
44 If x is +Inf, a domain error shall occur and an unspecified value is
46 returned.
47 If x is −Inf, a domain error shall occur and an unspecified value is
49 returned.
50 If the correct value is positive and too large to represent as a long
52 long, an unspecified value shall be returned. On systems that support
53 the IEC 60559 Floating-Point option, a domain error shall occur; other‐
54 wise, a domain error may occur.
55 If the correct value is negative and too large to represent as a long
57 long, an unspecified value shall be returned. On systems that support
58 the IEC 60559 Floating-Point option, a domain error shall occur; other‐
59 wise, a domain error may occur.
60
62 These functions shall fail if:
63 Domain Error
65 The x argument is NaN or ±Inf, or the correct value is not
66 representable as an integer.
67 If the integer expression (math_errhandling & MATH_ERRNO)
69 is non-zero, then errno shall be set to [EDOM]. If the
70 integer expression (math_errhandling & MATH_ERREXCEPT) is
71 non-zero, then the invalid floating-point exception shall
72 be raised.
73 These functions may fail if:
75 Domain Error
77 The correct value is not representable as an integer.
78 If the integer expression (math_errhandling & MATH_ERRNO)
80 is non-zero, then errno shall be set to [EDOM]. If the
81 integer expression (math_errhandling & MATH_ERREXCEPT) is
82 non-zero, then the invalid floating-point exception shall
83 be raised.
84 The following sections are informative.
86
88 None.
89
91 On error, the expressions (math_errhandling & MATH_ERRNO) and
92 (math_errhandling & MATH_ERREXCEPT) are independent of each other, but
93 at least one of them must be non-zero.
94
96 These functions provide floating-to-integer conversions. They round
97 according to the current rounding direction. If the rounded value is
98 outside the range of the return type, the numeric result is unspecified
99 and the invalid floating-point exception is raised. When they raise no
100 other floating-point exception and the result differs from the argu‐
101 ment, they raise the inexact floating-point exception.
102
104 None.
105
107 feclearexcept(), fetestexcept(), lrint()
108 The Base Definitions volume of POSIX.1‐2008, Section 4.19, Treatment of
110 Error Conditions for Mathematical Functions, <math.h>
111
113 Portions of this text are reprinted and reproduced in electronic form
114 from IEEE Std 1003.1, 2013 Edition, Standard for Information Technology
115 -- Portable Operating System Interface (POSIX), The Open Group Base
116 Specifications Issue 7, Copyright (C) 2013 by the Institute of Electri‐
117 cal and Electronics Engineers, Inc and The Open Group. (This is
118 POSIX.1-2008 with the 2013 Technical Corrigendum 1 applied.) In the
119 event of any discrepancy between this version and the original IEEE and
120 The Open Group Standard, the original IEEE and The Open Group Standard
121 is the referee document. The original Standard can be obtained online
122 at http://www.unix.org/online.html .
123 Any typographical or formatting errors that appear in this page are
125 most likely to have been introduced during the conversion of the source
126 files to man page format. To report such errors, see https://www.ker‐
127 nel.org/doc/man-pages/reporting_bugs.html .
128IEEE/The Open Group 2013 LLRINT(3P)