用C寫藍牙通訊程式：掃描、讀取、發送

在Linux下，通過bluez 藍牙庫可以用C語言輕松實作藍牙通信。在ubuntu下可以用 apt-get install libbluetooth-dev 安裝該庫。下面是幾個簡單示例。

一個簡單的掃描程式，得到周邊的藍牙從機裝置名和位址：

#include stdio.h>

#include stdlib.h>

#include unistd.h>

#include sys/socket.h>

#include bluetooth/bluetooth.h>

#include bluetooth/hci.h>

#include bluetooth/hci_lib.h>

int main(int argc, char **argv)

{

    inquiry_info *ii = NULL;

    int max_rsp, num_rsp;

    int dev_id, sock, len, flags;

    int i;

    char addr[19] = { 0 };

    char name[248] = { 0 };

    dev_id = hci_get_route(NULL);

    sock = hci_open_dev( dev_id );

    if (dev_id 0 || sock 0) {

        perror("opening socket");

        exit(1);

    }

    len = 8;

    max_rsp = 255;

    flags = IREQ_CACHE_FLUSH;

    ii = (inquiry_info*)malloc(max_rsp * sizeof(inquiry_info));

    num_rsp = hci_inquiry(dev_id, len, max_rsp, NULL, &ii, flags);

    if( num_rsp 0 ) perror("hci_inquiry");

    for (i = 0; i num_rsp; i++) {

        ba2str(&(ii+i)->bdaddr, addr);

        memset(name, 0, sizeof(name));

        if (hci_read_remote_name(sock, &(ii+i)->bdaddr, sizeof(name),

            name, 0) 0)

        strcpy(name, "[unknown]");

        printf("%s %s\n", addr, name);

    free( ii );

    close( sock );

    return 0;

}

讀和寫示例：

#include bluetooth/rfcomm.h>

    struct sockaddr_rc addr = { 0 };

    int s, status, len=0;

    char dest[18] = "00:12:01:31:01:13";

    char buf[256];

    // allocate a socket

    s = socket(AF_BLUETOOTH, SOCK_STREAM, BTPROTO_RFCOMM);

    // set the connection parameters (who to connect to)

    addr.rc_family = AF_BLUETOOTH;

    addr.rc_channel = (uint8_t) 1;

    str2ba( dest, &addr.rc_bdaddr );

    // connect to server

    status = connect(s, (struct sockaddr *)&addr, sizeof(addr));

    if(status){

        printf(" failed to connect the device!\n");

        return -1;

    do{

        len = read(s, buf, sizeof buf);

     if( len>0 ) {

         buf[len]=0;

         printf("%s\n",buf);

         write(s, buf, strlen(buf));

     }

    }while(len>0);

    close(s);