fclose - close a stream

       For an explanation of the terms used in this section, see attributes(7).
       ┌─────────────────────────────────────────────────────────────────────────────┬───────────────┬─────────┐
       │ Interface                                                                   │ Attribute     │ Value   │
       ├─────────────────────────────────────────────────────────────────────────────┼───────────────┼─────────┤
       │ fclose()                                                                    │ Thread safety │ MT-Safe │
       └─────────────────────────────────────────────────────────────────────────────┴───────────────┴─────────┘

       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 illegal pointer, or is a  descriptor
       already passed to a previous invocation of fclose().

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).

       C89, POSIX.1-2001.

       Standard C library (libc, -lc)

       fclose - close a stream

       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).

       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 another call to fclose()) to the stream results  in
       undefined behavior.

close(2), fcloseall(3), fflush(3), fileno(3), fopen(3), setbuf(3)

Linux man-pages 6.9.1                              2024-05-02                                          fclose(3)

       C11, POSIX.1-2008.

#include<stdio.h>intfclose(FILE*stream);