/* simple CAN application example  *  * open CAN and test the write(2) call * An calling option  decides if the CAN device is opend for * blocking or nonblocking write. */#include <stdio.h>#include <stdlib.h>#include <sys/types.h>#include <sys/stat.h>#include <sys/time.h>#include <sys/ioctl.h>#include <fcntl.h>#include <unistd.h>#include <string.h>#include <can4linux.h>#define STDDEV "can1"#define VERSION "1.1"/* #define TXBUFFERSIZE 256 */#define TXBUFFERSIZE 100#ifndef TRUE# define TRUE  1# define FALSE 0#endifint sleeptime            = 1000;	/* standard sleep time */int debug                = FALSE;int baud		 = -1;		/* dont change baud rate */int blocking		 = TRUE;	/* open() mode */long mcount		 = 100;		/* Number of messages to send *//* ----------------------------------------------------------------------- */void usage(char *s){static char *usage_text  = "\ Open CAN device and send CAN messages\n\ Default device is /dev/can1. \n\Options:\n\-d   - debug On\n\       swich on additional debugging\n\-T c - send max c number messages\n\-b baudrate (Standard uses value of /proc/sys/Can/baud)\n\-n   - non-blocking mode (default blocking)\n\-V   version\n\\n\";    fprintf(stderr, "usage: %s [options] [device]\n", s);    fprintf(stderr, usage_text);}/* -s sleep sleep in ms between write() calls in non-blocking mode\n\ *//************************************************************************* set_bitrate - sets the CAN bit rate*** Changing these registers only possible in Reset mode.** RETURN:**/int	set_bitrate(	int fd,			/* device descriptor */	int baud		/* bit rate */	){Config_par_t  cfg;volatile Command_par_t cmd;    cmd.cmd = CMD_STOP;    ioctl(fd, CAN_IOCTL_COMMAND, &cmd);    cfg.target = CONF_TIMING;     cfg.val1   = baud;    ioctl(fd, CAN_IOCTL_CONFIG, &cfg);    cmd.cmd = CMD_START;    ioctl(fd, CAN_IOCTL_COMMAND, &cmd);    return 0;}/************************************************************************* main - ***/int main(int argc,char **argv){int fd;int i, sent;int c;char *pname;extern char *optarg;extern int optind;long count;canmsg_t tx[TXBUFFERSIZE];char device[50];    pname = *argv;    /* parse command line */    while ((c = getopt(argc, argv, "b:dhs:nT:V")) != EOF) {	switch (c) {	    case 'b':		baud = atoi(optarg);		break;	    case 's':		sleeptime = atoi(optarg);		break;	    case 'd':		debug = TRUE;		break;	    case 'n':		blocking = FALSE;		break;	    case 'T':	    	mcount = atol(optarg);	    	break;	    case 'V':		printf("%s %s\n", argv[0], " V " VERSION ", " __DATE__ );		exit(0);		break;	    case 'D':		if (		    /* path ist starting with '.' or '/', use it as it is */			optarg[0] == '.'			|| 			optarg[0] == '/'			) {		    sprintf(device, "%s", optarg);	        } else {		    sprintf(device, "/dev/%s", optarg);		}		break;	    case 'h':	    default: usage(pname); exit(0);	}    }    /* look for additional arguments given on the command line */    if ( argc - optind > 0 ) {        /* at least one additional argument, the device name is given */        char *darg = argv[optind];	if (	    /* path ist starting with '.' or '/', use it as it is */		    darg[0] == '.'		    || 		    darg[0] == '/'		    ) {		sprintf(device, "%s", darg);	} else {	sprintf(device, "/dev/%s", darg);	}    } else {	sprintf(device, "/dev/%s", STDDEV);    }    if ( debug == TRUE ) {	printf("%s %s\n", argv[0], " V " VERSION ", " __DATE__ );	printf("(c) 1996-2006 port GmbH\n");	printf(" using canmsg_t with %d bytes\n", sizeof(canmsg_t));	printf(" max count %ld messages, %d with each write()\n",			mcount, TXBUFFERSIZE);	printf(" CAN device %s opened in %sblocking mode\n",		device, blocking ? "" : "non-");    }    sleeptime *= 1000;        if(blocking == TRUE) {	/* fd = open(device, O_RDWR); */	fd = open(device, O_RDWR);    } else {	fd = open(device, O_RDWR | O_NONBLOCK);    }    if( fd < 0 ) {	fprintf(stderr,"Error opening CAN device %s\n", device);	exit(1);    }    if (baud > 0) {	if ( debug == TRUE ) {	    printf("change Bit-Rate to %d Kbit/s\n", baud);	}	set_bitrate(fd, baud);    }    /* Initialize transmit messages */    for(i = 0; i < TXBUFFERSIZE; i++) {        sprintf( tx[i].data, "msg %4d", i);        tx[i].flags = 0;          tx[i].length = strlen(tx[i].data);          tx[i].id= i;    }    count = 0;    /* send messages, don't care about non-blocking mode */    while(1) {	*(long *)&tx[0].data = count;	sent = write(fd, &tx, TXBUFFERSIZE );	if(sent <= 0) {	    printf("sent %d;", sent); fflush(stdout);	    perror("sent");	}	count += sent;	if (count >= mcount) {		/* finished, but sleep to guarantee empty tx buffers */ 		sleep(1); exit(0);	}    }    close(fd);    return 0;}