Thread: how to send message(data) from c to c#?

hello
i wrote a simple programm in c and iwant to use c# for its gui(Graphic user interface) to show its data in C#.how can i do that ?
here is my c code:

Code:

//////////////////////////////

#include "stdio.h"
#include "winsock2.h"   //need winsock for inet_ntoa and ntohs methods
#include <string.h>
#define HAVE_REMOTE
#include "pcap.h"   //Winpcap :)

#pragma comment(lib , "ws2_32.lib") //For winsock
#pragma comment(lib , "wpcap.lib") //For winpcap

//some packet processing functions
void ProcessPacket(u_char* , int );
void print_ethernet_header(u_char*);
void PrintIpHeader(u_char*, int);
void print_udp_packet(u_char*, int);

//Ethernet Header
typedef struct ethernet_header
	{
	UCHAR dest[6];//6byte
	UCHAR source[6];//6byte
	USHORT type;//2byte
	} ETHER_HDR;

//Ip header (v4)
typedef struct ip_hdr
	{// for BYTE_ORDER == __LITTLE_ENDIAN
	unsigned char ip_header_len : 4; // 4-bit header length (in 32-bit words) normally=5 (Means 20 Bytes may be 24 also)
	unsigned char ip_version : 4; // 4-bit IPv4 version


	unsigned char ip_tos; // IP type of service
	unsigned short ip_total_length; // Total length
	unsigned short ip_id; // Unique identifier

	unsigned short R_DF_MF_FragmentOffset;

	unsigned char ip_ttl; // Time to live
	unsigned char ip_protocol; // Protocol(TCP,UDP etc)
	unsigned short ip_checksum; // IP checksum
	unsigned char ipSource[4]; // Source address
	unsigned char ipDestination[4]; // destination address
	} IPV4_HDR;


//UDP header
typedef struct udp_hdr
	{
	unsigned short source_port; // Source port no.
	unsigned short dest_port; // Dest. port no.
	unsigned short udp_length; // Udp packet length
	unsigned short udp_checksum; // Udp checksum (optional)
	} UDP_HDR;

int tcp = 0, udp = 0, icmp = 0, others = 0, igmp = 0, total = 0, i, j;

ETHER_HDR *ethhdr;

IPV4_HDR *iphdr;

UDP_HDR *udpheader;

u_char *data;

int main()
	{

	unsigned int i;
	unsigned int res;
	unsigned int chosenNumber;
	unsigned char  errbuf[PCAP_ERRBUF_SIZE], buffer[100];
	unsigned char *pkt_data;
	time_t seconds;
	struct tm tbreak;
	pcap_if_t *alldevs, *d;
	pcap_t *fp;
	struct pcap_pkthdr *header;


	/* The user didn't provide a packet source: Retrieve the local device list */
	if (pcap_findalldevs_ex(PCAP_SRC_IF_STRING, NULL, &alldevs, errbuf) == -1)
		{
	/*	printf("Error in pcap_findalldevs_ex: %s\n", errbuf);*/
		return -1;
		}

	i = 0;
	/* Print the list */
	for (d = alldevs; d; d = d->next)
		{
		++i;
		/*printf("%d. %s\n    ", ++i, d->name);

		if (d->description)
			{
			printf(" (%s)\n", d->description);
			}
		else
			{
			printf(" (No description available)\n");
			}*/
		}

	if (i == 0)
		{
		/*printf("No interfaces found! Exiting.\n");*/
		return -1;
		}

	//printf("Enter the interface number you would like to sniff : ");
	//scanf_s("%d", &chosenNumber);
	chosenNumber = 1;

	/* Jump to the selected adapter */
	for (d = alldevs, i = 0; i < chosenNumber - 1; d = d->next, i++);

	/* Open the device */
	if ((fp = pcap_open(d->name,
		100 /*snaplen*/,
		PCAP_OPENFLAG_PROMISCUOUS /*flags*/,
		20 /*read timeout*/,
		NULL /* remote authentication */,
		errbuf)
		) == NULL)
		{
		return -1;
		}

	//read packets in a loop :)
	while ((res = pcap_next_ex(fp, &header, &pkt_data)) >= 0)
		{
		if (res == 0)
			{
			// Timeout elapsed
			continue;
			}
		seconds = header->ts.tv_sec;
		localtime_s(&tbreak, &seconds);
		strftime(buffer, 80, "%d-%b-%Y %I:%M:%S %p", &tbreak);


		ProcessPacket(pkt_data, header->caplen);
		}

	if (res == -1)
		{
		return -1;
		}

	return 0;
	}

void ProcessPacket(u_char* Buffer, int Size)
	{
	//Ethernet header
	ethhdr = (ETHER_HDR *)Buffer;
	++total;

	//Ip packets
	if (ntohs(ethhdr->type) == 0x0800)
		{
		//ip header
		iphdr = (IPV4_HDR *)(Buffer + sizeof(ETHER_HDR));

		switch (iphdr->ip_protocol) //Check the Protocol and do accordingly...
			{

			case 17: //UDP Protocol
				udp++;
				print_udp_packet(Buffer, Size);
				break;

			default: //Some Other Protocol
				others++;
				break;
			}
		}

	}

/*
Print the Ethernet header
*/
void print_ethernet_header(u_char* buffer)
	{
	ETHER_HDR *eth = (ETHER_HDR *)buffer;
	eth->type = ntohs(eth->type);

	}

/*
Print the IP header for IP packets
*/
void PrintIpHeader(unsigned char* Buffer, int Size)
	{

	unsigned short swap_R_DF_MF_FOffset;
	int iphdrlen = 0;

	iphdr = (IPV4_HDR *)(Buffer + sizeof(ETHER_HDR));
	iphdrlen = iphdr->ip_header_len * 4;
	swap_R_DF_MF_FOffset = ntohs(iphdr->R_DF_MF_FragmentOffset);

	//print Ethernet header
	print_ethernet_header(Buffer);


	iphdr->ip_total_length=ntohs(iphdr->ip_total_length);
	iphdr->ip_id=ntohs(iphdr->ip_id);
	iphdr->ip_checksum= ntohs(iphdr->ip_checksum);
	//printf(" |-Reserved bit  Flag : %d\n", (swap_R_DF_MF_FOffset & 0x8000) >> 15);//(swap_R_DF_MF_FOffset& 0x8000)>0 ? 1:0
	//printf(" |-Dont Fragment Flag : %d\n", (swap_R_DF_MF_FOffset & 0x4000) >> 14);
	//printf(" |-More Fragment Flag : %d\n", (swap_R_DF_MF_FOffset & 0x2000) > 13);
	//printf(" |- Fragment Offset : %d\n", swap_R_DF_MF_FOffset & 0x1fff);
	//printf(" |-TTL : %d\n", (unsigned int)iphdr->ip_ttl);
	//printf(" |-Protocol : %d\n", (unsigned int)iphdr->ip_protocol);

	
	}


/*
Print the UDP header for UDP packets
*/
void print_udp_packet(u_char *Buffer, int Size)
	{
	int iphdrlen = 0, data_size = 0;

	iphdr = (IPV4_HDR *)(Buffer + sizeof(ETHER_HDR));

		//print ip header
		PrintIpHeader(Buffer, Size);
		iphdrlen = iphdr->ip_header_len * 4;
		udpheader = (UDP_HDR*)(Buffer + iphdrlen + sizeof(ETHER_HDR));   
		data = (Buffer + sizeof(ETHER_HDR)+iphdrlen + sizeof(UDP_HDR));
		data_size = (Size - sizeof(ETHER_HDR)-iphdrlen - sizeof(UDP_HDR));



		udpheader->source_port=ntohs(udpheader->source_port);
		udpheader->dest_port= ntohs(udpheader->dest_port);
		udpheader->udp_length= ntohs(udpheader->udp_length);
		udpheader->udp_checksum=ntohs(udpheader->udp_checksum);


	}

explanation:
i want to show each structures filed in a separate text box for example so far i can only print them in a console window in c .i don't know how i can send these to my c# application so that i can use them there.