segmentation fault

This is a discussion on segmentation fault within the C Programming forums, part of the General Programming Boards category; i have a data.raw file whose contents are 4 8 register 5 fine 3 afda 4 asd all i was ...

  1. #1
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    segmentation fault

    i have a data.raw file whose contents are
    4
    8 register
    5 fine
    3 afda
    4 asd

    all i was supposed to do is to copy the names into a structure array here is the code i have written which is showning segmentation fault on exectution
    Code:
    struct extract
    {
    	int p_num;
    	int p_len;
    	char *data;
    };
    int main(int argc , char * argv[]){
    	FILE *fp;
    	int n,i;
    	struct extract *e;
    	fp=fopen("data.raw","r");
    	fscanf(fp,"%d",&n);
    	e=(struct extract*)malloc(n*sizeof(struct extract));
    	e[0].p_num=n;
    	for(i=1;i<=n;i++){
    	fscanf(fp,"%d %s",&e[i].p_len,e[i].data);
    	printf("%d %s\n",e[i].p_len,e[i].data);
    	}
    	
    	return 0;
    }

  2. #2
    and the hat of wrongness Salem's Avatar
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    > for(i=1;i<=n;i++)
    An array of n slots has 0 to n-1 as subscripts.
    You're running off the end by 1 step.
    If you dance barefoot on the broken glass of undefined behaviour, you've got to expect the occasional cut.
    If at first you don't succeed, try writing your phone number on the exam paper.
    I support http://www.ukip.org/ as the first necessary step to a free Europe.

  3. #3
    and the hat of wrongness Salem's Avatar
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    You're also not allocating any space for each e[i].data either.
    If you dance barefoot on the broken glass of undefined behaviour, you've got to expect the occasional cut.
    If at first you don't succeed, try writing your phone number on the exam paper.
    I support http://www.ukip.org/ as the first necessary step to a free Europe.

  4. #4
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    thanks salem..
    it solved the problem

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