Using GPSD¶

sudo apt-get install gpsd gpsd-clients

# 启动
sudo systemctl start gpsd

# restart
sudo systemctl restart gpsd

# 停止
sudo systemctl stop gpsd

# 查询状态
sudo systemctl satus gpsd

# 停止
sudo systemctl stop gpsd
sudo systemctl stop gpsd.socket

sudo stty -F /dev/ttyUSB0 9600 cs8 -cstopb -parenb
sudo cat /dev/ttyUSB0

$ cat /etc/default/gpsd
# Devices gpsd should collect to at boot time.
# They need to be read/writeable, either by user gpsd or the group dialout.
DEVICES="/dev/ttyUSB0"

# Other options you want to pass to gpsd
GPSD_OPTIONS="-F /var/run/gpsd.sock"

# Automatically hot add/remove USB GPS devices via gpsdctl
USBAUTO="true"

cgps

gpsmon

sudo apt-get install libgps-dev libjansson-dev

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <gps.h>

#define GPSD_HOST "localhost"
#define GPSD_PORT "2947"

void print_gps_data(struct gps_data_t *gps_data) {
    if (gps_data->fix.mode >= MODE_2D) {
        printf("Latitude: %f\n", gps_data->fix.latitude);
        printf("Longitude: %f\n", gps_data->fix.longitude);
        printf("Altitude: %f\n", gps_data->fix.altitude);

        // Time is stored as a struct timespec, so we need to check if tv_sec is non-zero
        if (gps_data->fix.time.tv_sec != 0) {
            printf("Time: %ld.%09ld\n",
                   gps_data->fix.time.tv_sec, gps_data->fix.time.tv_nsec);
        } else {
            printf("Time: N/A\n");
        }
    } else {
        printf("GPS data not available.\n");
    }
}

int main(void) {
    struct gps_data_t gps_data;
    char buf[256];
    int ret;

    // Initialize GPSD library
    if (gps_open(GPSD_HOST, GPSD_PORT, &gps_data) != 0) {
        fprintf(stderr, "Could not connect to GPSD\n");
        return 1;
    }

    // Configure GPSD to provide data
    gps_stream(&gps_data, WATCH_ENABLE, NULL);

    while (1) {
        // Read GPS data with appropriate arguments
        ret = gps_read(&gps_data, buf, sizeof(buf));
        if (ret == -1) {
            fprintf(stderr, "Error reading GPS data\n");
            break;
        }
        print_gps_data(&gps_data);
        sleep(1);  // Update interval
    }

    gps_stream(&gps_data, WATCH_DISABLE, NULL);
    gps_close(&gps_data);

    return 0;
}