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s = socket(PF_CAN, SOCK_RAW, CAN_RAW);
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s = socket(PF_CAN, SOCK_DGRAM, CAN_BCM);
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»ù±¾µÄCANÖ¡½á¹¹ÌåºÍÌ×½Ó×ÖµØÖ·½á¹¹Ì嶨ÒåÔÚinclude/linux/can.h£º
/*
* À©Õ¹¸ñʽʶ±ð·ûÓÉ 29 λ×é³É¡£Æä¸ñʽ°üº¬Á½¸ö²¿·Ö£º11 λ»ù±¾ ID¡¢18 λÀ©Õ¹ ID¡£
* Controller Area Network Identifier structure *
* bit 0-28 : CANʶ±ð·û (11/29 bit)
* bit 29 : ´íÎóÖ¡±êÖ¾ (0 = data frame, 1 = error frame) * bit 30 : Ô¶³Ì·¢ËÍÇëÇó±êÖ¾ (1 = rtr frame)
* bit 31 :Ö¡¸ñʽ±êÖ¾ (0 = standard 11 bit, 1 = extended 29 bit) */
typedef __u32 canid_t;
struct can_frame {
canid_t can_id; /* 32 bit CAN_ID + EFF/RTR/ERR flags */ __u8 can_dlc; /* Êý¾Ý³¤¶È: 0 .. 8 */ __u8 data[8] __attribute__((aligned(8))); };
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¾ÍÏñPF_PACKETÌ×½Ó×ÖÒ»Ñù£¬sockaddr_can½á¹¹ÌåÒ²ÓнӿڵÄË÷Òý£¬Õâ¸öË÷Òý°ó¶¨ÁËÌض¨½Ó¿Ú£º
struct sockaddr_can { sa_family_t can_family; int can_ifindex; union {
/* transport protocol class address info (e.g. ISOTP) */ struct { canid_t rx_id, tx_id; } tp;
/* reserved for future CAN protocols address information */ } can_addr; };
Ö¸¶¨½Ó¿ÚË÷ÒýÐèÒªµ÷ÓÃioctl()£¨±ÈÈç¶ÔÓÚûÓдíÎó¼ì²éCAN_RAWÌ×½Ó×Ö£©:
int s;
struct sockaddr_can addr; struct ifreq ifr;
s = socket(PF_CAN, SOCK_RAW, CAN_RAW);
strcpy(ifr.ifr_name, \
ioctl(s, SIOCGIFINDEX, &ifr);
addr.can_family = AF_CAN;
addr.can_ifindex = ifr.ifr_ifindex;
bind(s, (struct sockaddr *)&addr, sizeof(addr));
(..)
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