Whats wrong with my C program?

This is a discussion on Whats wrong with my C program? within the C Programming forums, part of the General Programming Boards category; Code: #include <stdio.h> #include <stdlib.h> #include <string> int main(int argc, char *argv[]) { char name[]=""; int length=0, i=0; printf("Input your ...

  1. #1
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    Whats wrong with my C program?

    Code:
    #include <stdio.h>
    #include <stdlib.h>
    #include <string>
    
    int main(int argc, char *argv[])
    {
    char name[]="";
    int length=0, i=0;
    
    printf("Input your name: ");
    scanf("%c", name);
    length= strlen(name);
    
    printf("Your name is: ");
    while (i < length) {
    printf("%c", name[i]);
    i++; }
    
    printf("\n\n");
    system("pause");
    return EXIT_SUCCESS;
    }
    Compiler: MingW(IDE: Bloodshed Dev-C++ 4.01)
    Web Site: Zoo Crew
    Forums: Zoo Boards
    E-mail: goldenbunny84@hotmail.com

    "Do you wanna go to jail or do you wanna go home?!?!" - Alonzo(Training Day)

  2. #2
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    scanf(%c", &name) will only give you a single character.

    char name[80];

    gets(name);

    printf("The name was %s", name);

    or scanf("%s", name);
    Last edited by ronin; 06-30-2002 at 09:49 PM.
    I haven't used a compiler in ages, so please be gentle as I try to reacclimate myself. :P

  3. #3
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    I know about the strings. I was trying to make the loop for.
    Compiler: MingW(IDE: Bloodshed Dev-C++ 4.01)
    Web Site: Zoo Crew
    Forums: Zoo Boards
    E-mail: goldenbunny84@hotmail.com

    "Do you wanna go to jail or do you wanna go home?!?!" - Alonzo(Training Day)

  4. #4
    Guest Sebastiani's Avatar
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    "I know about the strings..."
    Apparently not!

    char name[]="";

    The compiler is obligated to allocate precisely ONE character for this string! And that is for the null-terminator!! So pay attention:

    char name[] = "Joe"; //...compiler allocates 4 bytes - No More!

    char name[100]; //...excellent...100 bytes alloc'd

    change that one line of code and your for() loop will work.

    P.S.: If you want to see for yourself, just print the value of strlen...

  5. #5
    End Of Line Hammer's Avatar
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    Originally posted by ronin
    scanf(%c", &name) will only give you a single character.

    char name[80];

    gets(name);

    printf("The name was %s", name);

    or scanf("%s", name);
    Please, never recommend the use of gets(), it's a function that should've been got rid of a long time ago....
    When all else fails, read the instructions.
    If you're posting code, use code tags: [code] /* insert code here */ [/code]

  6. #6
    Registered User pinko_liberal's Avatar
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    Smile

    A stack smasher who doesnt like gets )

  7. #7
    End Of Line Hammer's Avatar
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    Originally posted by pinko_liberal
    A stack smasher who doesnt like gets )
    Well, you use it, and I'll abuse it
    When all else fails, read the instructions.
    If you're posting code, use code tags: [code] /* insert code here */ [/code]

  8. #8
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    Shouldn't you be including <string.h>, not simply <string>?

  9. #9
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    where is ...

    EXIT_SUCCESS defined???

  10. #10
    Code Goddess Prelude's Avatar
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    >EXIT_SUCCESS defined???
    Along with EXIT_FAILURE, EXIT_SUCCESS is defined in stdlib.h.

    -Prelude
    My best code is written with the delete key.

  11. #11
    ATH0 quzah's Avatar
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    Originally posted by Prelude
    >EXIT_SUCCESS defined???
    Along with EXIT_FAILURE, EXIT_SUCCESS is defined in stdlib.h.

    -Prelude
    Hey, you better watch it. You don't want to be too helpful. Someone might get angry for you enlighten--er--bad mouthing them...

    Quzah.
    Hope is the first step on the road to disappointment.

  12. #12
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    why not gets()

    what's the problem with gets()??

  13. #13
    Im back! shaik786's Avatar
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    char name[80];

    gets(name);

    printf("The name was %s", name);

    or scanf("%s", name);
    >what's the problem with gets()??
    Absolutely nothing, unless the user entered a string longer than 79 characters. That's because you have allocated only 80 bytes for the variable 'name', and gets() would read from the stdin and copy the buffer to this variable. If the length of the copy exceeded the limit allocated to this variable, there would be a risk of writing the data to some other memory location, which might be used by some other application/function, probably corrupting the data there and crashing the program using it. Or, your own program might terminate with an error due to to access of memory not allocated to/by your program. So, it's always safer to use fgets(), with the FILE * argument of it set to stdin, where you can limit the number of characters to be read to some limit of your choice.

  14. #14
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    Hey guys, I took your advice but my program still doesn't work. I have it, along with the .exe file in a zip. So here it is to download..........
    Attached Files Attached Files
    Compiler: MingW(IDE: Bloodshed Dev-C++ 4.01)
    Web Site: Zoo Crew
    Forums: Zoo Boards
    E-mail: goldenbunny84@hotmail.com

    "Do you wanna go to jail or do you wanna go home?!?!" - Alonzo(Training Day)

  15. #15
    Im back! shaik786's Avatar
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    >Hey guys, I took your advice but my program still doesn't work. I have it, along with the .exe file in a zip. So here it is to download..........
    How about pasting the code here instead of attaching it as an attachment. I'm sure there are many more like me who cannot download it for various number of reasons. And about the .exe, it's not at all safe to download anything like that on the internet, so I doubt if anybody would really download your attachment.

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