The rewind function is equivalent to fseek (file_ptr, 0, SEEK_
    SET). You can use the rewind function with either record or
    stream files.

    A successful call to rewind clears the error indicator for the
    file.

    The ANSI C standard defines rewind as not returning a value;
    therefore, the function prototype for rewind is declared with a
    return type of void. However, since a rewind can fail, and since
    previous versions of the Compaq C RTL have declared rewind to
    return an int, the code for rewind does return 0 on success and
    -1 on failure.

    See also fseek.