strcmp

This is a discussion on strcmp within the C++ Programming forums, part of the General Programming Boards category; i have assigned a character array of 10 to hold a password. then i ask for the user to input ...

  1. #1
    Registered User
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    May 2002
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    7

    strcmp

    i have assigned a character array of 10 to hold a password.

    then i ask for the user to input a password and then compares the new password with the original to validate its authenticity.

    However i cant get strcmp to retun 0 (zero) although the new password is entered exactly like the old one.

    The while loop simply outputs *'s to the screen instead of echoing the password entered....i dont know if its the problem...


    char original_password[10]="member";

    char new_password[10];

    cout<<"enter your password\n";
    int i = 0;

    while( ( temp_mem_password[i] = getch() ) != '\r' )
    {
    cout << "*";

    i++;
    }


    compare=strcmp(mem_password,temp_mem_password);
    cout<<"compare:"<<compare;

  2. #2
    Registered User
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    May 2002
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    317
    1. getch(); returns a keycode -> that is a number!

    Code:
    int temp;
    	int compare;
    	string original_password="member"; 
    
    	string new_password; 
    
    	cout<<"enter your password\n"; 
    	int i = 0; 
    
    	while( ( temp = getch() ) != '\r' ) 
    	{ 
    		new_password += char(temp); //convert to character
    		cout << "*"; 
    		i++; 
    	}
    	if(original_password == new_password)
    		cout<<"correct!";
    You need to use an if statement here with the '==' operator because strcmp does not like the two different types of strings. However the code works fine. If you have any questions just ask.

  3. #3
    End Of Line Hammer's Avatar
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    6,231

    Re: strcmp

    Originally posted by stanleyw
    i have assigned a character array of 10 to hold a password.
    <--snip-->
    .... then if I hex dump your binary, I will know your password.

    Never store passwords in programs this way, it's far too easy to get at them! Encrypt it, or build it dynamically or something.
    When all else fails, read the instructions.
    If you're posting code, use code tags: [code] /* insert code here */ [/code]

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