1FERROR(3)                  Linux Programmer's Manual                 FERROR(3)
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NAME

6       clearerr, feof, ferror - check and reset stream status
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SYNOPSIS

9       #include <stdio.h>
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11       void clearerr(FILE *stream);
12       int feof(FILE *stream);
13       int ferror(FILE *stream);
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DESCRIPTION

16       The function clearerr() clears the end-of-file and error indicators for
17       the stream pointed to by stream.
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19       The function feof() tests the  end-of-file  indicator  for  the  stream
20       pointed  to by stream, returning nonzero if it is set.  The end-of-file
21       indicator can be cleared only by the function clearerr().
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23       The function ferror() tests the error indicator for the stream  pointed
24       to  by stream, returning nonzero if it is set.  The error indicator can
25       be reset only by the clearerr() function.
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27       For nonlocking counterparts, see unlocked_stdio(3).
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RETURN VALUE

30       The feof() function returns nonzero if the end-of-file indicator is set
31       for stream; otherwise, it returns zero.
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33       The ferror() function returns nonzero if the error indicator is set for
34       stream; otherwise, it returns zero.
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ERRORS

37       These functions should not fail and do not set errno.
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ATTRIBUTES

40       For an  explanation  of  the  terms  used  in  this  section,  see  at‐
41       tributes(7).
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43       ┌────────────────────────────────────────────┬───────────────┬─────────┐
44       │Interface                                   │ Attribute     │ Value   │
45       ├────────────────────────────────────────────┼───────────────┼─────────┤
46       │clearerr(), feof(), ferror()                │ Thread safety │ MT-Safe │
47       └────────────────────────────────────────────┴───────────────┴─────────┘
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CONFORMING TO

50       The  functions  clearerr(),  feof(),  and ferror() conform to C89, C99,
51       POSIX.1-2001, and POSIX.1-2008.
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NOTES

54       POSIX.1-2008 specifies that these functions shall not change the  value
55       of errno if stream is valid.
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SEE ALSO

58       open(2), fdopen(3), fileno(3), stdio(3), unlocked_stdio(3)
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COLOPHON

61       This  page  is  part of release 5.13 of the Linux man-pages project.  A
62       description of the project, information about reporting bugs,  and  the
63       latest     version     of     this    page,    can    be    found    at
64       https://www.kernel.org/doc/man-pages/.
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68                                  2021-03-22                         FERROR(3)