Netzlaufwerke verbinden C

#include <stdio.h>
#include <string.h>
#include <stdlib.h>

#define EXIT	0
#define FAILURE	1
#define MAX		100
#define CLS		system("cls"); 

char authpuffer[150];
char user[16];
char passwd[31];

char *devices = {  "net use T: \\\\172.16.0.2\\MOVIES",  
                     "net use V: \\\\172.16.0.2\\MOVIES1",  
                     "net use W: \\\\172.16.0.2\\MOVIES2",  
                     "net use X: \\\\172.16.0.2\\PROGRAMME",  
                     "net use Y: \\\\172.16.0.2\\DIV",  
                     "net use S: \\\\172.16.0.2\\Music" };  

int connection(void);
int disconnection(void);
void status(void);
void load(void);
short auth(dev_id);


int system();

int main(void)
	{

		int menuop;

		system("Color 0a && Title Secure Fileserver Client ver.1.31");  
		load();
		system("CLS");  

		ret : puts("\a"); 	CLS;  
	

		printf("\n\n  --   Net-device-Client   --   \n");          


		puts("\n\n");  

		printf(" [1] Connection\n\n");  

		printf(" [2] Disconnect\n\n");  

		printf(" [3] Server-Status\n\n");  

		printf("  Exit\n\n");  


		printf("Input:");  

		scanf("%1i", &menuop);  
		fflush(stdin);
	

		switch(menuop) {

			case 1:	connection();
					goto ret;

			case 2: disconnection();
					goto ret;

			case 3: status();
					goto ret;

			case 0:	return EXIT;

					default:fprintf(stderr,"falsche eingabe !!");  
				
		}

     goto ret;
}

// Connection 

int connection()
	{
		char yn;
		int i, x;
//		short reply;

		printf("\a");  
		CLS;
		printf("\nNetzlaufwerke verbinden ? (y/n)\n\n");  
		scanf("%1c", &yn);  
	
		if(yn == 'y'){  

		CLS;

		printf("\n\nBitte Authentifizieren\n");  

		printf("\nUsername eingeben:\n");  
		scanf("%15s",&user);  
		fflush(stdin);
		printf("\nPassword eingeben:\n");  
		scanf("%30s", &passwd);  
		fflush(stdin);

		system("net use /persistent:no >nul");  

		for(x=0 ; x<6 ; x++) {
			if(auth(devices[x])) {
				fprintf(stderr,"ein netzlaufwerk verbindung gescheitert ...");  
			}

		}

				fprintf(stderr,"netzlaufwerk erfolgreich verbunden ...");  



				for(i = 0;(i < 800000000l); i++);
						;

				return EXIT;


			}

			else if(yn == 'n');{  
				return EXIT;
			}

		printf("falsches zeichen");  

		for(i = 0;(i < 800000000l); i++);
			;
		

		  return EXIT;
		
	}




// Disconnect


int disconnection()
	{
		char yn;
		long i;
		CLS;
			puts("\n");  
			sp:printf("\a");   
			printf("\n\nNetzlaufwerke trennen ? (y/n)\n\n");  
			scanf("%1c", &yn);  
			fflush(stdin);
			CLS;
	
		if(yn == 'y'){  

			system("net use T: /delete >nul");  
			system("net use V: /delete >nul");  
			system("net use W: /delete >nul");  
			system("net use X: /delete >nul");  
			system("net use Y: /delete >nul");  

			if( !(system("net use S: /delete >nul"))){  

					printf("Netzlaufwerke wurden getrennt ...");  

			}else{

					CLS;
					fprintf(stderr,"\nFehler bei der Netzlaufwerk trennung");  
			}

				for(i = 0;i < 800000000; i++)
						;
				return EXIT;
			}
			
			else if(yn == 'n'){  

				return EXIT;
			}

			
			printf("FALSCHES ZEICHEN");  
			for(i = 0;i < 800000000; i++);						;
			CLS;
			goto sp;
				
	}




//Server-Status


void status(void)
	{
	long i;
	CLS;
	if(system("ping -n 1 -w 10 172.16.0.2>nul") == 0)  
			printf("\n\n Server 172.16.0.2 Online \n\n");  
				else
			printf("\n\n Server 172.16.0.2 Offline\n\n");  

		for(i = 0;(i++ < 800000000l);)
			;
	}


// Loading-Funktion


void load(void)
	{
	char buffer= "LOADING";  
	int zahl = 0;

			do
			{
				printf("%d%%", zahl);  
				CLS;
				printf("\n\n\n\n\n\t%s\t", &buffer);  
				zahl++;
			}
		while(zahl < MAX);

	}


 
short auth(char *device)
	{


		strcpy(authpuffer, device);
		strcat(authpuffer, " ");  
		strcat(authpuffer, passwd);
		strcat(authpuffer, " /u:");   
		strcat(authpuffer, user);
		strcat(authpuffer, " >NUL");  

		if(!(system(authpuffer))){
		
			return EXIT;

		} else {
			
			return FAILURE;

		}

	}