1 #include "unp.h"
2
3 void
sig_alrm(int signo)4 sig_alrm(int signo)
5 {
6 }
7
8 int
main(int argc,char ** argv)9 main(int argc, char **argv)
10 {
11 int sockfd, n;
12 struct sockaddr_in servaddr;
13 struct itimerval val;
14 fd_set rset, wset;
15
16 if (argc != 2)
17 err_quit("usage: a.out <IPaddress>");
18
19 if ( (sockfd = socket(AF_INET, SOCK_STREAM, 0)) < 0)
20 err_sys("socket error");
21
22 bzero(&servaddr, sizeof(servaddr));
23 servaddr.sin_family = AF_INET;
24 servaddr.sin_port = htons(13); /* echo server */
25 Inet_pton(AF_INET, argv[1], &servaddr.sin_addr);
26
27 /* Set interval timer to go off before 3WHS completes */
28 Signal(SIGALRM, sig_alrm);
29 val.it_interval.tv_sec = 0;
30 val.it_interval.tv_usec = 0;
31 val.it_value.tv_sec = 0;
32 val.it_value.tv_usec = 50000; /* 50 ms */
33 if (setitimer(ITIMER_REAL, &val, NULL) == -1)
34 err_sys("setitimer error");
35
36 again:
37 if (connect(sockfd, (SA *) &servaddr, sizeof(servaddr)) < 0) {
38 if (errno == EINTR) {
39 #ifdef notdef
40 goto again; /* second call to connect() -> EADDRINUSE */
41 #endif
42 #ifdef notdef
43 printf("interrupted system call\n");
44 exit(0);
45 #endif
46 } else
47 err_sys("connect error");
48 }
49
50 FD_ZERO(&rset);
51 FD_SET(sockfd, &rset);
52 wset = rset;
53 sleep(4);
54 n = Select(sockfd+1, &rset, &wset, NULL, NULL);
55 printf("select returned %d\n", n);
56 if (FD_ISSET(sockfd, &rset))
57 printf("socket is readable\n");
58 if (FD_ISSET(sockfd, &wset))
59 printf("socket is writable\n");
60
61 str_cli(stdin, sockfd); /* do it all */
62
63 exit(0);
64 }
65