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Seg Faulting C. Where?

Some where in my code i am causing a memory violation and my program crashes. The word which is in the text file is test.

Can anyone help?

//This is going to be hangman
#include <stdio.h>
main()
{
char answer[1000];
char guess;
int bool;
int i;

FILE *file;
file = fopen("answer", "r");
if (file == NULL)
{
printf("No File To Be Processed \n");
}
else
{
printf ("File Found \n");
while(fgets(answer,1000,file)!=NULL)
{
printf("%s",answer);
}
}

printf ("Welcome To Hangman \n");
printf ("Please Pick A Letter \n");
guess = getchar();

do
{
i=i+1;
if(guess == answer[i])
{
printf("Correct Guess");
bool = 0;
}
else
{
printf("%c", answer[i]);
}
}
while(bool=1 || i < 3);

}

You are going overbounds on your answer[] array.

what you mean its allocated to 1000 characters and i am only using 4 (test), what should i do if you are right?

Hint: Your loop logic is incorrect.

Thanx for the hint, but as i am so new to C, i wouldn't know where or what i am looking for. Can you shed some more light on it, Thankyou.

Re: Seg Faulting C. Where?

Quote:

Originally posted by DaveyB
Some where in my code i am causing a memory violation and my program crashes. The word which is in the text file is test.

Can anyone help?

[...]
}
while(bool=1 || i < 3);

}

Just a quick glance, so I'm not sure if this is the only mistake (sorry for sounding up-nosed :-))
but I think it should read

> while(bool==1 || i < 3); <

Code:

#include <stdio.h>



int main()  /* Doesn't matter too much, but strictly main() should

              * return an int.

              */

{

    char answer[1000];

    char guess;

    int bool;

    int i;



    FILE *file;

    file = fopen("answer", "r");

    if (file == NULL)

    {

        printf("No File To Be Processed \n");

    }

    else

    {

        printf ("File Found \n");

        while(fgets(answer,1000,file)!=NULL)

        {

            printf("%s",answer);

        }

    }



    /* Note: here answer[] will contain the last line of the file */



    printf ("Welcome To Hangman \n");

    printf ("Please Pick A Letter \n");

    guess = getchar();



    i = 0; /* Note: better to allways give a var a starting value */



    do

    {

        i=i+1;  /* Note: you're skipping first character here! */

        if(guess == answer[i])

        {

            printf("Correct Guess");

            bool = 0;

        }

        else

        {

            printf("%c", answer[i]);

        }

    }

    while(bool=1 || i < 3); /* You're assigning (=) 1 to bool, not comparing (==)

                            * the value of assignment will also be 1, so the

                            * loop continues indefinately, increasing i each time.

                            * When this is fixed, the loop will still continue

                            * indefinately if the 'guess' is not in 'answer[]'.

                            * In that case bool will not turn to 0, so will be

                            * 1 all the time, thus running the loop again.

                            * 

                            *  It may be better to check for answer[i] != '\0'

                            */



    return 0;  /* return int from main() */



}

Compiling with -Wall option, would have given you a clue for at least one of the problems.

THANKYOU: I've done everthing you said and it still segfaults any ideas? :THANKYOU

//This is going to be hangman
#include <stdio.h>
int main()
{
char answer[1000];
char guess;
int bool;
int count;

//this is where i load all my variables to make my do loop work
bool = 1;

//reads in "test" from text file
FILE *file;
file = fopen("answer", "r");
if (file == NULL)
{
printf("No File To Be Processed \n");
}
else
{
printf ("File Found \n");
while(fgets(answer,1000,file)!=NULL)
{
printf("%s",answer);
}
}

//starts hangman
printf ("Welcome To Hangman \n");
printf ("Please Pick A Letter \n");
guess = getchar();

//validation to make sure the answer is correct to the inputted answer
do
{
count++;
if(guess == answer[count])
{
printf("Correct Guess");
bool = 0;
}
else
{
printf("%c", answer[count]);
}
}
while((bool == 1) || (count < 3));

return 0;
}

Quote:

char answer[1000];
char guess;
int bool;
int count;

//this is where i load all my variables to make my do loop work
bool = 1;

//reads in "test" from text file
FILE *file;

This is bad. All variable declarations should go at the beginning of a code block. Declaring FILE *file after you do bool = 1 is a bad thing to do and will cause a lot of compilers to fail with an error.

Please use code tags when posting code.

Also, you don't initialize count. Automatic variables start with a garbage value so they must be initialized before you use them.

I just took a quick glance through your new code and you're still NOT giving all your variables a starting value. count is not being set to 0 before the increment operator (++) is being used. Hence, count could be any value and hence could very well be bigger than 1000 and hence crashing your program with a seg fault error.

Like what itsme86 is saying, good programming practise is to do all declaration of variables at the start quickly followed by their initialization to a starting value.