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#include <stdio.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <string.h>
#include <unistd.h>
#include <stdlib.h>
#define host "192.168.2.3"
#define port 8888
int f(struct in_addr *saddr, const char *data, const size_t data_len) {
int sockfd;
struct sockaddr_in addr;
sockfd = socket(AF_INET, SOCK_STREAM, 0);
if (sockfd < -1) {
perror("socket");
return 1;
}
memset(&addr, 0, sizeof(addr));
addr.sin_family = AF_INET;
addr.sin_port = htons(port);
addr.sin_addr = *saddr;
if (connect(sockfd, (struct sockaddr *)&addr, sizeof(addr))) {
perror("connect");
return 1;
}
write(sockfd, data, data_len);
close(sockfd);
return 0;
}
int main(int argc, char **argv) {
struct in_addr saddr;
const char *data = "GET / HTTP/1.0\r\n\r\n";
const size_t data_len = strlen(data);
if (argc != 2) {
fprintf(stderr, "Usage: %s count\n", *argv);
return 1;
}
if (!inet_aton(host, &saddr)) {
perror("inet_aton");
return 1;
}
int count = atoi(argv[1]);
const char dot = '.';
unsigned fails;
while (--count >= 0) {
if (!(count % 10)) {
write(STDOUT_FILENO, &dot, sizeof(dot));
}
if (f(&saddr, data, data_len)) {
if (++fails > 10) break;
} else
fails /= 2;
}
putchar('\n');
return 0;
}
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