Error expected identifier before ' &' token

Hullo everyone, i have been trying to work around this error for a while but i just can not get it fixed. thought i would ask for some help on this forum. I have a struct called alt_dev_s with one of the elements as int(*open) (alt_fd* fd. const char* name, int flags, int mode) to open the file descriptor

when i try to access the element in my main function i get the above error. Here is my code sample. Thanks in advance!!

Code:

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#define ERGO_CMD_GET_ADDRESS  0x11
#define ERGO_CMD_RUN_DATA      0x40
#define ERGO_CMD_SET_WATT    0x51
#define UART_MAX_DATA      20

/*Global Variables*/
ergo_run_data_t ergo_run_data;
u_int8_t ergo_adr_int;

/* External Functions that are called in the main function*/

int altera_16550_uart_read_fd(alt_fd* fd, char* ptr, int len);
int altera_16550_uart_write_fd(alt_fd* fd, const char* buffer, int space);
int altera_16550_uart_ioctl_fd(alt_fd* fd, int req, void* arg);
int altera_16550_uart_close_fd(alt_fd* fd);
//int (*open) (alt_fd* fd, const char* name, int flags, int mode);
void ergo_get_address();
void ergo_get_run_data(void);
void ergo_set_watt(u_int8_t ergo_adr_int, u_int8_t watt);
void ergo_reset(u_int8_t ergo_adr_int);
void ergo_break(void);


int main()
{
    alt_fd* fd;
    struct alt_dev_s alt_dev;
 /*Open File Descriptor*/

// I am getting the error on this line

 alt_dev -> &(open) (&(alt_fd) {"/dev/ttyUSB0"}, &(const char) {ttyUSB0},0,O_RDWR|O_NOCTTY|O_NONBLOCK); 
      //Error Handling
        if ( fd < 0 )
        {
        printf("Error beim oeffnen");
        }

    return 0;
}

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You are confusing struct alt_dev_s and alt_dev types.
Function call should look like this:

Code:

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alt_fd *fd = NULL; // needs to be initialized with some value
struct alt_dev_s alt_dev;
int file_desc = alt_dev.open(fd, "/dev/ttyUSB0", 0, O_RDWR | O_NOCTTY | O_NONBLOCK);
if (file_desc < 0)
{
    printf("Error beim oeffnen");
}

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