// start
#include <stdio.h>
#include <stdlib.h>
#include <pcap.h> /* GIMME a libpcap plz! */
#include <errno.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
int main(int argc, char **argv)
{
char *dev; /* name of the device to use */
char *net; /* dot notation of the network address */
char *mask;/* dot notation of the network mask */
int ret; /* return code */
char errbuf[PCAP_ERRBUF_SIZE];
bpf_u_int32 netp; /* ip */
bpf_u_int32 maskp;/* subnet mask */
struct in_addr addr;
/* ask pcap to find a valid device for use to sniff on */
dev = pcap_lookupdev(errbuf);
/* error checking */
if(dev == NULL)
{
printf("%s\n",errbuf);
exit(1);
}
/* print out device name */
printf("DEV: %s\n",dev);
/* ask pcap for the network address and mask of the device */
ret = pcap_lookupnet(dev,&netp,&maskp,errbuf);
if(ret == -1)
{
printf("%s\n",errbuf);
exit(1);
}
/* get the network address in a human readable form */
addr.s_addr = netp;
net = inet_ntoa(addr);
if(net == NULL)/* thanks Scott :-P */
{
perror("inet_ntoa");
exit(1);
}
printf("NET: %s\n",net);
/* do the same as above for the device's mask */
addr.s_addr = maskp;
mask = inet_ntoa(addr);
if(mask == NULL)
{
perror("inet_ntoa");
exit(1);
}
printf("MASK: %s\n",mask);
return 0;
}
// end
I try to compile the file (ldev.c) in fedora 7 using the command
>>
gcc ldev.c -lpcap but the following errors have occcured :-
ldev.c:3:46: error: pcap.h: No such file or directory
ldev.c: In function ‘main’:
ldev.c:15: error: ‘PCAP_ERRBUF_SIZE’ undeclared (first use in this function)
ldev.c:15: error: (Each undeclared identifier is reported only once
ldev.c:15: error: for each function it appears in.)
ldev.c:16: error: ‘bpf_u_int32’ undeclared (first use in this function)
ldev.c:16: error: expected ‘;’ before ‘netp’
ldev.c:17: error: expected ‘;’ before ‘maskp’
ldev.c:21: warning: assignment makes pointer from integer without a cast
ldev.c:34: error: ‘netp’ undeclared (first use in this function)
ldev.c:34: error: ‘maskp’ undeclared (first use in this function)
what should i do to remove the errors ?
