1FERAISEEXCEPT(3P) POSIX Programmer's Manual FERAISEEXCEPT(3P)
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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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12 feraiseexcept — raise floating-point exception
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15 #include <fenv.h>
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17 int feraiseexcept(int excepts);
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20 The functionality described on this reference page is aligned with the
21 ISO C standard. Any conflict between the requirements described here
22 and the ISO C standard is unintentional. This volume of POSIX.1‐2017
23 defers to the ISO C standard.
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25 The feraiseexcept() function shall attempt to raise the supported
26 floating-point exceptions represented by the excepts argument. The
27 order in which these floating-point exceptions are raised is unspeci‐
28 fied, except that if the excepts argument represents IEC 60559 valid
29 coincident floating-point exceptions for atomic operations (namely
30 overflow and inexact, or underflow and inexact), then overflow or
31 underflow shall be raised before inexact. Whether the feraiseexcept()
32 function additionally raises the inexact floating-point exception when‐
33 ever it raises the overflow or underflow floating-point exception is
34 implementation-defined.
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37 If the argument is zero or if all the specified exceptions were suc‐
38 cessfully raised, feraiseexcept() shall return zero. Otherwise, it
39 shall return a non-zero value.
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42 No errors are defined.
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44 The following sections are informative.
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47 None.
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50 The effect is intended to be similar to that of floating-point excep‐
51 tions raised by arithmetic operations. Hence, enabled traps for float‐
52 ing-point exceptions raised by this function are taken.
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55 Raising overflow or underflow is allowed to also raise inexact because
56 on some architectures the only practical way to raise an exception is
57 to execute an instruction that has the exception as a side-effect. The
58 function is not restricted to accept only valid coincident expressions
59 for atomic operations, so the function can be used to raise exceptions
60 accrued over several operations.
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63 None.
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66 feclearexcept(), fegetexceptflag(), fetestexcept()
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68 The Base Definitions volume of POSIX.1‐2017, <fenv.h>
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71 Portions of this text are reprinted and reproduced in electronic form
72 from IEEE Std 1003.1-2017, Standard for Information Technology -- Por‐
73 table Operating System Interface (POSIX), The Open Group Base Specifi‐
74 cations Issue 7, 2018 Edition, Copyright (C) 2018 by the Institute of
75 Electrical and Electronics Engineers, Inc and The Open Group. In the
76 event of any discrepancy between this version and the original IEEE and
77 The Open Group Standard, the original IEEE and The Open Group Standard
78 is the referee document. The original Standard can be obtained online
79 at http://www.opengroup.org/unix/online.html .
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81 Any typographical or formatting errors that appear in this page are
82 most likely to have been introduced during the conversion of the source
83 files to man page format. To report such errors, see https://www.ker‐
84 nel.org/doc/man-pages/reporting_bugs.html .
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88IEEE/The Open Group 2017 FERAISEEXCEPT(3P)