Thread: Problem I can't seem to solve

Originally Posted by Dave_Sinkula

Why binary mode for strings? If you really need binary mode, shouldn't you use fread instead of fgets?

I use binary because a txt file would enable users to go look into the txt file. Ok one could say they just have to open the file in notepad to see it too.... but not everyone knows that. + I still need to find a way to "encrypt" the writing to a file.


thanks for the feedback, I'll change the loop with feof like the tutorial explains...

here are the answers to your questions:

Originally Posted by Dave_Sinkula

Do you really need clrscr and conio.h?

yes I do... before entering this function, the screen needs to be cleared because they already got an intro function with a header, menu ...
anyway this is just esthetics...

Originally Posted by Dave_Sinkula

[edit]

Code:

fgets(temp_user,sizeof(user)+1,login);

Read one less than the string can hold (even when accounting for the null character), but disguise it to look like it's reading one more than it should?

well this is odd I must admit... but without the +1 the watch tells me it reads in "[blank spaces]... user" (it omits the last character.. here a 1 )
by doing the +1 it reads the info correctly...: "[blankspaces]....user1"

Originally Posted by Dave_Sinkula

Kinda the same thing here:

Code:

scanf("%15s", user);

I put this because I made a limit that max. 15 characters are to be used for login and password...

+ I was hoping by putting this like that... when a user enters for instance user1

it would store it like this " user1"

thus the strcmp between this and the sequence read out of the file would be equal
and thus result in "login ok"

Originally Posted by Dave_Sinkula

What's \i?

Code:

else printf("\incorrect\n");

sorry typo after having paste it into this box

Originally Posted by Dave_Sinkula

Is login a FILE* or a function?

Code:

int login(void){

char user[15];
char pass[15];
char temp_user[17];
char temp_pass[17];
int sw_ok=1;
FILE *login;

good point...
I renamed the function to "inloggen" (dutch)

this function is called out from the main function..



thanks for the feedback...

thanks for the code and alternative way...

I've been looking into how to do it also
and came up with this:


(sorry if the code is lame... I'm still quite new at C)
also the printf's are in dutch...

Code:

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


int inloggen(void){

char user[15];
char pass[15];
char **temp_user,**temp_pass,lijn[31],c='o'; //15+15+1
//int's voor de lussen...
int sw_ok=1, sw_user=1, sw_pass=1,sw_gevonden=0,lengte=0,i=0;
FILE *login;


printf("\t**********************************************\n");
printf("\t*                  Login                     *\n");
printf("\t**********************************************\n");

login=fopen("users.dat", "rb");
fscanf(login,"%*s");
	 while(!feof(login))
	 {	  lengte++;
		  fscanf(login,"%*s");
	 }
	 rewind(login);
	 temp_user=calloc(sizeof(char*),lengte);
	 temp_pass=calloc(sizeof(char*),lengte);
	 for(i=0;i<lengte;i++)
	 {   fscanf(login,"%s",lijn);
		  temp_user[i]=malloc(16);
		  strncpy(temp_user[i],lijn,15);
		  fscanf(login,"%s",lijn);
		  temp_pass[i]=malloc(16);
		  strncpy(temp_pass[i],lijn,15);
	 }
	 fclose(login);

while (sw_ok)
{
	while(sw_user)
	{
		printf("Gebruikersnaam: ");
		scanf("%15s%c", user,&c);
		if(c!='\n')
		{
			printf("Deze gebruikersnaam is te lang. U kan enkel een gebruikersnaam gebruiken van 15 karakters.\n");
			scanf("%*[^\n]%*c");
		}
		else sw_user=0;
	}

	while(sw_pass)
	{
		printf("Geef uw paswoord: ");
		scanf("%15s%c",pass,&c);
		if(c!='\n')
		{
			printf("Foutief paswoord...(te lang, max 15 karakters)\n");
			scanf("%*[^\n]%*c");
		}
		else sw_pass=0;
	}


for(i=0;i<lengte;i++){
	if (strcmp(temp_user[i], user) == 0 && strcmp(temp_pass[i], pass) ==0){
							sw_ok=0;
							sw_gevonden=1;
				}
				else  {
					sw_user=1;
					sw_pass=1;
					}
	 }//einde for lus
if (sw_gevonden)
{
printf("***********************\n");
printf("*     Toegang OK      *\n");
printf("***********************\n");
menu();
}
else printf("Foute gebruikersnaam of paswoord\nProbeer opnieuw AUB\n");
}
	return 0;
}