fclose(3) Library Functions Manual fclose(3)
NAME
fclose - close a stream
LIBRARY
Standard C library (libc, -lc)
SYNOPSIS
#include <stdio.h>
int fclose(FILE *stream);
DESCRIPTION
The fclose() function flushes the stream pointed to by stream (writing
any buffered output data using fflush(3)) and closes the underlying file
descriptor.
The behaviour of fclose() is undefined if the stream parameter is an il-
legal pointer, or is a descriptor already passed to a previous invoca-
tion of fclose().
RETURN VALUE
Upon successful completion, 0 is returned. Otherwise, EOF is returned
and errno is set to indicate the error. In either case, any further ac-
cess (including another call to fclose()) to the stream results in unde-
fined behavior.
ERRORS
EBADF The file descriptor underlying stream is not valid.
The fclose() function may also fail and set errno for any of the errors
specified for the routines close(2), write(2), or fflush(3).
ATTRIBUTES
For an explanation of the terms used in this section, see attributes(7).
┌────────────────────────────────────────────┬───────────────┬─────────┐
│ Interface │ Attribute │ Value │
├────────────────────────────────────────────┼───────────────┼─────────┤
│ fclose() │ Thread safety │ MT-Safe │
└────────────────────────────────────────────┴───────────────┴─────────┘
STANDARDS
C11, POSIX.1-2008.
HISTORY
C89, POSIX.1-2001.
NOTES
Note that fclose() flushes only the user-space buffers provided by the C
library. To ensure that the data is physically stored on disk the ker-
nel buffers must be flushed too, for example, with sync(2) or fsync(2).
SEE ALSO
close(2), fcloseall(3), fflush(3), fileno(3), fopen(3), setbuf(3)
Linux man-pages 6.9.1 2024-05-02 fclose(3)
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