Get a message in raw frame mode (blocking)
#include <sys/can_dcmd.h> #define CAN_DEVCTL_RX_FRAME_RAW_BLOCK __DIOF(_DCMD_MISC, CAN_CMD_CODE + 10, struct can_msg)
| Argument | Value |
|---|---|
| filedes | A file descriptor that you obtained by opening the device. This must be for a receive mailbox (e.g., /dev/can1/rx2). |
| dcmd | CAN_DEVCTL_RX_FRAME_RAW_BLOCK |
| dev_data_ptr | A pointer to a struct can_msg |
| n_bytes | sizeof(struct can_msg) |
| dev_info_ptr | NULL |
This command gets the next valid received message from the queue when the driver is in raw frame mode. If there are no messages, the command blocks. Not all CAN drivers support raw mode.
None.
A filled-in can_msg structure, which is defined in <sys/can_dcmd.h> as follows:
#define CAN_MSG_DATA_MAX 0x8 /* Max number of data bytes in a CAN message
as defined by CAN spec */
/* Extended CAN Message */
typedef struct can_msg_ext {
uint32_t timestamp; /* CAN message timestamp */
uint32_t is_extended_mid; /* 1=29-bit MID, 0=11-bit MID */
uint32_t is_remote_frame; /* 1=remote frame request, 0=data frame */
} CAN_MSG_EXT;
/* CAN Message */
typedef struct can_msg {
/* Pre-allocate CAN messages to the max data size */
uint8_t dat[CAN_MSG_DATA_MAX]; /* CAN message data */
uint8_t len; /* Actual CAN message data length */
uint32_t mid; /* CAN message identifier */
CAN_MSG_EXT ext; /* Extended CAN message info */
} CAN_MSG;
CAN_DEVCTL_READ_CANMSG_EXT, CAN_DEVCTL_RX_FRAME_RAW_NOBLOCK, CAN_DEVCTL_TX_FRAME_RAW, CAN_DEVCTL_WRITE_CANMSG_EXT
devctl() in the QNX Neutrino C Library Reference
canctl in the Utilities Reference