Linux application Programming: Socket Common API summary __ block chain

1: Code

#include <stdio.h> #include <unistd.h> #include <stdlib.h> #include <string.h> #include < errno.h> #include <sys/socket.h> #include <netinet/in.h> #include <arpa/inet.h> #include <
netdb.h> #include <sys/ioctl.h> #include <sys/socket.h> #include <net/if.h>//extern int h_errno;
Char interfaceipaddr[50];
        int get_interface_ipaddr (char *ethname) {int inet_sock;
        struct Ifreq IFR;
        Inet_sock = socket (af_inet, SOCK_DGRAM, 0);
        strcpy (Ifr.ifr_name, ethname);
					if (IOCTL (Inet_sock, SIOCGIFADDR, &AMP;IFR) < 0) {perror ("bind");
		    Exit (Exit_failure);
sprintf (interfaceipaddr, "%s", Inet_ntoa ((struct sockaddr_in*) & (IFR.IFR_ADDR)));
		} void Getinterfaceinfo (char* ethinterface) {int i,sock_fd;
		struct Ifreq ifreq;
		Char mac[32];
		Char ipbuf[16];
		int rcvbuf_size,sndbuf_size,type=0;
    socklen_t size; if (Sock_fd=socket (af_inet,sock_stream,0) <0) {perror ("error");
    Exit (Exit_failure);
	} size=sizeof (Sndbuf_size);
	GetSockOpt (sock_fd,sol_socket,so_sndbuf,&sndbuf_size,&size);
	printf ("sndbuf_size=%d size=%d\n", sndbuf_size,size);
	Size=sizeof (rcvbuf_size);
	GetSockOpt (sock_fd,sol_socket,so_rcvbuf,&rcvbuf_size,&size);
	printf ("rcvbuf_size=%d size=%d\n", rcvbuf_size,size);
	Size=sizeof (type);
	GetSockOpt (sock_fd,sol_socket,so_type,&type,&size);
    printf ("Socket type=%d\n", type);
    strcpy (Ifreq.ifr_name,ethinterface);
        if (IOCTL (sock_fd,siocgifhwaddr,&ifreq) <0) {perror ("error:");
    Exit (Exit_failure);
    For (i=0 i<6; i++) {sprintf (Mac+3*i, "%02x:", (unsigned char) ifreq.ifr_hwaddr.sa_data[i]);
    } mac[17]= ';
    printf ("mac:%s\n", MAC);
        if (IOCTL (sock_fd,siocgifaddr,&ifreq) <0) {perror ("error:");
    Exit (Exit_failure); printf ("IP:%s\n", Inet_ntoa ((struct sockaddr_in*) &ifrEQ.IFR_ADDR)) (-&GT;SIN_ADDR));
return 0;
	} void Gethostbyipadrr (char* ipaddr) {U_int addr;
	struct Hostent *hp;
	Char **p;
	struct Ifreq ifreq;
		if (ipaddr = = NULL) {printf ("usage:ip-address\n");
	Exit (Exit_failure);
		} if ((int) (addr = inet_addr (ipaddr)) = = 1) {printf ("ip-address must be of the form a.b.c.d\n");
	Exit (Exit_failure);
	} hp=gethostbyaddr ((char *) &addr, sizeof (addr), af_inet);
		if (HP = NULL) {printf ("Host information for%s no found \ n", ipaddr);
	Exit (Exit_failure);
		for (P = hp->h_addr_list; *p!=0;p++) {struct in_addr in;
		Char **q;
		memcpy (&in.s_addr, *p, sizeof (IN.S_ADDR));
		printf ("%s\t%s", Inet_ntoa (in), hp->h_name);
		for (q=hp->h_aliases;*q!= 0; q++) printf ("%s\t", *q);
	printf ("\ n");
	} void Ipaddrconvert () {in_addr_t netaddr;
	struct IN_ADDR net_addr,ret;
	Char buf[128];
	memset (buf, ' n ', 128);
	NETADDR=INET_ADDR ("192.168.68.128");

	NET_ADDR.S_ADDR=NETADDR; printf ("inet_addr (192.168.68.128) =0x%x\ n ", inet_addr (" 192.168.68.128 "));

	printf ("Inet_network (192.168.68.128) =0x%x\n", Inet_network ("192.168.68.128"));
	printf ("Inet_ntoa (net)%s\n", Inet_ntoa (NET_ADDR));
	Inet_aton ("192.168.68.128", &ret);

	printf ("Test inet_aton,then Inet_ntoa (ret)%s\n", Inet_ntoa (ret));
	Inet_pton (Af_inet, "192.168.68.128", &ret);
	Inet_ntop (af_inet,&ret,buf,128);
printf ("buf=%s\n", buf);
	} void gethostbyname (char *hostname) {char *ptr,**pptr;
	Char Str[inet_addrstrlen];

	struct Hostent *hptr;
		{ptr = hostname; if ((hptr = gethostbyname (ptr)) = = NULL) {printf ("GetHostByName error for Host:%s:%s", PTR, Hstrerror (H_errno)
			);
		Exit (Exit_failure);
		printf ("Official hostname:%s\n", hptr->h_name);
		For (pptr=hptr->h_aliases; *pptr!= NULL; pptr++) {printf ("\talias:%s\n", *pptr);
				Switch (hptr->h_addrtype) {Case af_inet:pptr = hptr->h_addr_list; for (; *pptr!= NULL; pptr++) printf ("\taddress:%s\n", Inet_ntop (Hptr->h_addRtype, *pptr, str, sizeof (str));

			Break
				Default:printf ("Unknown address type");
		Break
		}} void Showinterfaceipinfo (char *ethname) {/* initializes the network to obtain information for the current network device */int i;
		int sock;
		struct sockaddr_in sin;
		struct Ifreq IFR;
		unsigned char g_eth_name[16];
		unsigned char g_macaddr[6];
		unsigned int g_subnetmask;
		unsigned int g_ipaddr;
		unsigned int g_broadcast_ipaddr;
		Sock = socket (af_inet, SOCK_DGRAM, 0);
		if (sock = = 1) {perror ("socket");
	    } strcpy (G_eth_name,ethname);
		strcpy (Ifr.ifr_name, g_eth_name);


		printf ("Eth name:\t%s\n", g_eth_name);
		Gets and prints the network card address if (IOCTL (sock, SIOCGIFHWADDR, &AMP;IFR) < 0) {perror ("ioctl");

		} memcpy (G_macaddr, Ifr.ifr_hwaddr.sa_data, 6);
		printf ("local mac:\t");
		for (i=0;i<5;i++) {printf ("%.2x:", G_macaddr[i]);

		printf ("%.2x\n", G_macaddr[i]);
		Gets and prints the IP address if (IOCTL (sock, SIOCGIFADDR, &AMP;IFR) < 0) {perror ("ioctl"); memcpy (&sin, &ifr.ifr_addr, sizeof (SIN));
		G_IPADDR = sin.sin_addr.s_addr;

		printf ("Local%s:\t%s\n", G_eth_name, Inet_ntoa (SIN.SIN_ADDR));
		Gets and prints the broadcast address if (IOCTL (sock, SIOCGIFBRDADDR, &AMP;IFR) < 0) {perror ("ioctl");
		} memcpy (&sin, &ifr.ifr_addr, sizeof (sin));
		G_BROADCAST_IPADDR = sin.sin_addr.s_addr;

		printf ("broadcast:\t%s\n", Inet_ntoa (SIN.SIN_ADDR));
		Gets and prints the subnet mask if (IOCTL (sock, Siocgifnetmask, &AMP;IFR) < 0) {perror ("ioctl");
		} memcpy (&sin, &ifr.ifr_addr, sizeof (sin));
		G_subnetmask = sin.sin_addr.s_addr;

		printf ("subnetmask:\t%s\n", Inet_ntoa (SIN.SIN_ADDR));
Close (sock);
    } usageerror (const char *progname, const char *msg) {if (msg!= NULL) {fprintf (stderr, '%s ', msg);
    } fprintf (stderr, "Usage:%s [options] parameter\n", progname);
    fprintf (stderr, "Usage:%s [N:I:P:FH] parameter\n", progname);				fprintf (stderr, "Usage:%s-n [hostName];"
    to Execute:gethostbyname () \ n ", progname);  				fprintf (stderr, "Usage:%s-i [ipaddr];"to EXECUTE:GETHOSTBYIPADRR () \ n ", progname);	fprintf (stderr, "Usage:%s-p [interface;eth0/eth1];"
    to Execute:getinterfaceinfo () \ n ", progname);	fprintf (stderr, "Usage:%s-f [addr convert function];
    to Execute:ipaddrconvert () \ n ", progname);

    fprintf (stderr, "Usage:%s-h; to Execute:help\n", progname);
Exit (Exit_failure);
	int main (int argc, char **argv) {int opt;
	if (argc==1) {usageerror (argv[0], NULL); #if 0 printf ("\n\n*********************************************************************************************
	\ n ");
	System ("cat/etc/hosts"); printf ("****************************************************************************************************\n
\ n "); #endif while (opt = getopt (argc, argv, "N:I:P:FH"))!=-1} {switch (opt) {case ' n ': if (optarg!=null) {p
				rintf ("optopt:%c:%s\n", Optopt,optarg);
			gethostbyname (OPTARG);
			else {usageerror (argv[0], NULL);
		} break;
			Case ' I ': if (optarg!=null) {	printf ("Optopt:%c:%s\n", Optopt,optarg);
			GETHOSTBYIPADRR (OPTARG);
			else {usageerror (argv[0], NULL);
		} break;
				Case ' P ': if (optarg!=null) {printf ("optopt:%c:%s\n", Optopt,optarg);
				Getinterfaceinfo (OPTARG);
			Showinterfaceipinfo (OPTARG);
			else {usageerror (argv[0], NULL);
		} break;
			Case ' F ': Ipaddrconvert ();
		Break
		Default:usageerror (Argv[0], NULL);
} exit (0);
 }

2: Execution Results