fclose

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< c‎ | io
 
 
File input/output
Types and objects
Functions
File access
Direct input/output
Unformatted input/output
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Formatted input
(C99)(C99)(C99)(C11)(C11)(C11)     
 
Defined in header <stdio.h>
int fclose( FILE *stream );

Closes the given file stream. Any unwritten buffered data are flushed to the OS. Any unread buffered data are discarded.

Whether or not the operation succeeds, the stream is no longer associated with a file, and the buffer allocated by setbuf or setvbuf, if any, is also disassociated and deallocated if automatic allocation was used.

The behavior is undefined if the value of the pointer stream is used after fclose returns.

Parameters

stream - the file stream to close

Return value

0 on success, EOF otherwise

Example

#include <stdio.h>
#include <stdlib.h>
 
int main(void)
{
    const char* fname = "/tmp/unique_name.txt"; // or tmpnam(NULL);
    int is_ok = EXIT_FAILURE;
 
    FILE* fp = fopen(fname, "w+");
    if (!fp) {
        perror("File opening failed");
        return is_ok;
    }
    fputs("Hello, world!\n", fp);
    rewind(fp);
 
    int c; // note: int, not char, required to handle EOF
    while ((c = fgetc(fp)) != EOF) // standard C I/O file reading loop
        putchar(c);
 
    if (ferror(fp))
        puts("I/O error when reading");
    else if (feof(fp)) {
        puts("End of file is reached successfully");
        is_ok = EXIT_SUCCESS;
    }
 
    fclose(fp);
    remove(fname);
    return is_ok;
}

Possible output:

Hello, world!
End of file is reached successfully

References

  • C11 standard (ISO/IEC 9899:2011):
  • 7.21.5.1 The fclose function (p: 304)
  • C99 standard (ISO/IEC 9899:1999):
  • 7.19.5.1 The fclose function (p: 270)
  • C89/C90 standard (ISO/IEC 9899:1990):
  • 4.9.5.1 The fclose function

See also

opens a file
(function)
open an existing stream with a different name
(function)