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#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <pthread.h>
#include <string.h>
#include <arpa/inet.h>
char*
check_string(char buffer[1024], int n)
{
char* string = "yes";
int i;
for(i = 0; i < n; ++i) {
if (buffer[i] != 'V' && buffer[i] != 'F') {
strcpy(string, "no");
break;
}
}
return string;
}
int
main(int argc, char* argv[])
{
int sockfd, clientfd;
struct sockaddr_in addr;
socklen_t addrlen;
char buffer[1024];
char* result;
int n;
if ((sockfd = socket(PF_INET, SOCK_STREAM, 0)) == -1) {
perror("socket");
exit(1);
}
addr.sin_addr.s_addr = INADDR_ANY;
addr.sin_port = htons(3333);
addr.sin_family = AF_INET;
addrlen = sizeof(addr);
if (bind(sockfd, (struct sockaddr*) &addr, addrlen) == -1) {
perror("bind");
exit(1);
}
if (listen(sockfd, 1) == -1) {
perror("listen");
exit(1);
}
while (1) {
if ((clientfd = accept(sockfd, (struct sockaddr*) &addr, &addrlen)) == -1) {
perror("accept");
exit(1);
}
if ((n = read(clientfd, buffer, sizeof(buffer))) == -1) {
perror("read");
goto clientclose;
}
result = check_string(buffer, n);
printf("%s\n", result);
clientclose:
close(clientfd);
}
close(sockfd);
return 0;
}
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