/*****************+*************************
    * memio - Functions to read/write memory *
 ******************************************/

/* Return Memory File Pointer Contents    *
 * Args: mp - memory file pointer         *
 * Returns: Tuple                         *
             memory pointer address LSB   * 
             memory pointer address MSB   */
char maddr();

/* Open Memory File                       *
 *   Sets starting address to read/write  *
 * Args: zp - zero page pointer address   *
 *       &a - base address to read/write  *
 * Returns: memory file pointer           *
 *          0 if base address is invalid  */
char mopen();

/* Close Memory File                      *
 *   Writes EOF at current memory byte    *
 *   and cleares memory pointer           *
 * Args: mp - memory file pointer         *
 * Returns: 0 if successful               *
            255 if memory pointer invalid */
char mclose();

/* End of Memory File                     *
 *   Checks for EOF in next memory byte   *
 * Args: mp - memory file pointer         *
 * Returns: 0 if not at end of file       *
            255 if end of file reached    */
char meof();

/* Memory File Error                      *
 *   Checks for valid memory pointer      *
 * Args: mp - memory file pointer         *
 * Returns: 0 if successful               *
            255 if memory pointer invalid */
char merror();

/* Flush File Buffer                      *
 *   Writes EOF at current memory byte    *
 * Args: mp - memory file pointer         *
 * Returns: 0 if successful               *
            255 if memory pointer invalid */
char mflush();

/* Read Character from Memory File        *
 * Args: mp - memory file pointer         *
 * Returns: ASCII value of character      *
 *          system dependent garbage      *
            character if past end of file *
            255 if memory pointer invalid */
char mgetc();

/* Write Character to Memory File         *
 * Args: mp - memory file pointer         *
 *       c - ASCII character to write     *
 * Returns: 0 if successful               *
            255 if memory pointer invalid */
char mputc(); 

/* Read String from Memory File           *
 *   Buffers up to 128 characters         *
 *   until C/R or EOF is found            *
 * Args: mp - memory file pointer         *
 *       &s - string read from memory     *
 * Returns: Tuple                         *
 *           length of string             *
 *           (255 if error during read)   *
 *           last character read          */
char mgets(); 

/* Write String to Memory File            *
 *   Writes up to 128 characters of a     *
 *   null terminated string               *
 * Args: mp - memory file pointer         *
 *       &s - string to write from        *
 * Returns: ending position in string     *
 *          255 if error during write     */
char mputs();

/* Write Line to Memory File              *
 *   Write String to File followed by C/R *
 * Args: mp - memory file pointer         *
 *       &s - string to print from        *
 * Returns: ending position in string     *
 *          255 if error during write     */
char mputln();

/* Set Destination Array for fread()      *
 * Args: &a - Destination array           */
void mdst();

/* Read Bytes from Memory File            *
 *   Reads until End of Memory is reached *
 * Args: mp - memory file pointer         *
 *       n - number of bytes to read      *
 * Returns: number of bytes read          */
char mread(); 

/* Set Source Array for fwrite()          *
 * Args: &a - Source array                */
void msrc();

/* Write Bytes to Memory File             *
 * Args: mp - memory file pointer         *
 *       n - number of bytes to write     *
 * Returns: number of bytes written       */
char mwrite();