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#include <arpa/inet.h>
#include <assert.h>
#include <fcntl.h>
#include <stdint.h>
#include <stdio.h>
#include <string.h>
#include <sys/socket.h>
int rdate_main(int argc, char **argv) {
int fd = socket(AF_INET, SOCK_STREAM, 0);
if (fd < 0) {
perror("socket");
return 1;
}
struct addrinfo *result = NULL;
struct addrinfo hints;
memset(&hints, 0, sizeof(hints));
hints.ai_socktype = SOCK_STREAM;
hints.ai_protocol = 0;
hints.ai_canonname = NULL;
hints.ai_addr = NULL;
hints.ai_next = NULL;
int rc = getaddrinfo("time-d-g.nist.gov", "37", &hints, &result);
if (-1 == rc) {
fprintf(stderr, "Error in getaddrinfo()\n");
return 1;
}
if (connect(fd, (struct sockaddr *)result->ai_addr, result->ai_addrlen) < 0) {
perror("connect");
return 1;
}
uint32_t t;
read(fd, &t, sizeof(t));
t = ntohl(t);
close(fd);
int64_t unix_time = (t - 2208988800) * 1000;
int clock_fd = open("/dev/clock", O_RDWR);
int64_t current;
dprintf(clock_fd, "%lld", unix_time);
close(clock_fd);
return 0;
}
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