FCLOSE(3)                                                               Linux Programmer's Manual                                                              FCLOSE(3)

NAME
       fclose - close a stream

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.

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 access (including an‐
       other call to fclose()) to the stream results in undefined 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 │
       └──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┴───────────────┴─────────┘

CONFORMING TO
       POSIX.1-2001, POSIX.1-2008, C89, C99.

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 kernel  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)

GNU                                                                            2021-03-22                                                                      FCLOSE(3)