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#include <stdio.h>
#include <strings.h>
#include <errno.h>
#include <sys/types.h>
#include <sys/time.h>
#include <netinet/in.h>
#include <netdb.h>
#include "arlib.h"
#ifndef lint
static char sccsid[] = "@(#)sample.c 1.1 12/21/92 (C)1992 Darren Reed. ASYNC DNS";
#endif
char line[512];
int lookup = 0, seq = 0;
long expire = 0;
main()
{
struct in_addr adr;
struct timeval tv2;
fd_set rd;
long now;
char *s;
int afd, nfd, pid = getpid(), del;
afd = ar_init(ARES_INITLIST|ARES_CALLINIT|ARES_INITSOCK);
(void)printf("afd = %d pid = %d\n",afd, pid);
while (1)
{
(void)printf("Host =>");
(void)fflush(stdout);
*line = '\0';
FD_ZERO(&rd);
FD_SET(0,&rd);
FD_SET(afd,&rd);
now = time(NULL);
if (expire >= now)
{
tv2.tv_usec = 0;
tv2.tv_sec = expire - now;
nfd = select(FD_SETSIZE, &rd, NULL, NULL, &tv2);
}
else
nfd = select(FD_SETSIZE, &rd, NULL, NULL, NULL);
if (FD_ISSET(0, &rd))
{
if (!fgets(line, sizeof(line) - 1, stdin))
exit(0);
if (s = index(line, '\n'))
*s = '\0';
}
if (isalpha(*line))
{
(void)printf("Asking about [%s] #%d.\n",line, ++seq);
(void)ar_gethostbyname(line, (char *)&seq,
sizeof(seq));
lookup++;
}
else if (isdigit(*line))
{
(void)printf("Asking about IP#[%s] #%d.\n",
line, ++seq);
adr.s_addr = inet_addr(line);
(void)ar_gethostbyaddr(&adr, (char *)&seq,
sizeof(seq));
lookup++;
}
if (lookup)
(void)printf("Waiting for answer:\n");
if (FD_ISSET(afd, &rd))
(void)waitonlookup(afd);
del = 0;
expire = ar_timeout(time(NULL), &del, sizeof(del));
if (del)
{
(void)fprintf(stderr,"#%d failed\n", del);
lookup--;
}
}
}
printhostent(hp)
struct hostent *hp;
{
struct in_addr ip;
int i;
(void)printf("hname = %s\n", hp->h_name);
for (i = 0; hp->h_aliases[i]; i++)
(void)printf("alias %d = %s\n", i+1, hp->h_aliases[i]);
for (i = 0; hp->h_addr_list[i]; i++)
{
bcopy(hp->h_addr_list[i], (char *)&ip, sizeof(ip));
(void)printf("IP# %d = %s\n", i+1, inet_ntoa(ip));
}
}
int waitonlookup(afd)
int afd;
{
struct timeval delay;
struct hostent *hp;
fd_set rd;
long now;
int nfd, del;
waitloop:
FD_ZERO(&rd);
now = time(NULL);
if (expire >= now)
delay.tv_sec = expire - now;
else
delay.tv_sec = 1;
delay.tv_usec = 0;
FD_SET(afd, &rd);
FD_SET(0, &rd);
nfd = select(FD_SETSIZE, &rd, 0, 0, &delay);
if (nfd == 0)
return 0;
else if (FD_ISSET(afd, &rd))
{
del = 0;
hp = ar_answer(&del, sizeof(del));
(void)printf("hp=%x seq=%d\n",hp,del);
if (hp)
{
(void)printhostent(hp);
if (!--lookup)
return 1;
}
}
if (FD_ISSET(0, &rd))
return 2;
return 0;
}
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