Thread: Problem with "pointer from integer without a cast"

Hi, I have yet another problem after spending a full day today working on my program. What I am trying to do is to read a textfile, and put the values within the textfile into proper categories within the struct. So in this case I have built a struct containing the members, which are categories that I want the values to be in.
Here is my struct:

Code:

struct database_input {
  int categoryA;
  int categoryB;
  double categoryC;
  int categoryD;

};

where the format of one line of the data
(the textfile consists of alot of lines of the same format):

1.3.1.2 = 3.97438e-05 121 1

in which I want the first number (1.3.1.2) to go into the first category and the second number (3.97438e-05) to go in the 2nd category and so on.
What I did to get 1.3.1.2 to be and int is to establish a loop to skip the periods and only read 1312 as a string, then typecast it back to int. For the second number, since everything is in e-05, I only read the number up to 3.97438, and then I typecast to double and divide by 10000.

Here is how I call the function in main:

Code:

int main()
{
struct database_input data[99999];
initializing_structs(data); //for setting all values to 0
read_input( inputname , data);
...

the function code is:

Code:

void read_input( FILE *ifp, struct database_input *data)
{
int i=0;
char number = NULL;
char *categoryA_number = NULL;

char  *categoryC_f = NULL;
double categoryC_number;

char *categoryB_number;

while( i<99999 && feof(ifp) != 1)
	{
	while( number != ' ')
	{
		fscanf( ifp, number);
		if (number != '.')
		strcat(categoryA_number, number);
	}

	data[i].categoryA = (int)*categoryA_number;
	ifp = ifp+2;
	number = NULL;

	while( number != 'e')
	{
		fscanf( ifp,number);
		strcat(categoryC_f, number);
	}
	
	categoryC_number = (double)*categoryC_f;
	data[i].categoryC = categoryC_number/10000;
	ifp = ifp+5;
	number = NULL;
	
	while( number != ' ')
	{
		fscanf( ifp, number);
		if (number != '.')
		strcat(categoryB_number, number);
	}

	
	data[i].categoryB = (int)*categoryB_number;
	ifp = ifp+1;
	number = NULL;
	fscanf( ifp, number);
	data[i].categoryD = (int)number;
	number = NULL;
	
	while( number != '\n')
	{
		fscanf( ifp, number);
		ifp++;
	}
	
	i++;
	}
}

I know this is a long post, but please keep on reading...

The program when compiled, had many warnings, like:

projectmain.c:91: warning: conflicting types for ‘initializing_structs’
projectmain.c:54: warning: previous implicit declaration of ‘initializing_structs’ was here
projectmain.c:107: warning: conflicting types for ‘read_input’
projectmain.c:55: warning: previous implicit declaration of ‘read_input’ was here
projectmain.c: In function ‘read_input’:
projectmain.c:109: warning: initialization makes integer from pointer without a cast
projectmain.c:121: warning: passing argument 2 of ‘fscanf’ makes pointer from integer without a cast
projectmain.c:123: warning: passing argument 2 of ‘strcat’ makes pointer from integer without a cast
projectmain.c:128: warning: assignment makes integer from pointer without a cast
projectmain.c:132: warning: passing argument 2 of ‘fscanf’ makes pointer from integer without a cast
projectmain.c:133: warning: passing argument 2 of ‘strcat’ makes pointer from integer without a cast
projectmain.c:139: warning: assignment makes integer from pointer without a cast
projectmain.c:143: warning: passing argument 2 of ‘fscanf’ makes pointer from integer without a cast
projectmain.c:145: warning: passing argument 2 of ‘strcat’ makes pointer from integer without a cast
projectmain.c:152: warning: assignment makes integer from pointer without a cast

When I run the program, it just went into segmentation error. I already tried to simplify the function as much as possible, but it still ends up with a long code. Can somebody please help me to find what was wrong with this code, and if possible, ways to fix it? Since the code that I have wrote is a bit confusing, don't hold back in asking me questions about how the logic of the code works.

as for not feof(), I am having difficulties in inplementing the fix in the faq into my code since I am not reading the whole line, I am reading from character to character.

Many Thanks.

Sounds like an issue with default promotions. Do you prototype the function before you call it? The line numbers are meaningless without full context, BTW.

The first 3 almost certainly relate to not having a prototype for the function before trying to call it.

All the rest relate to your completely broken fscanf calls.

> struct database_input data[99999];
You might want to reconsider putting such a large array on the stack.

> while( i<99999 && feof(ifp) != 1)
1. Don't use feof() in a control loop - see the FAQ
2. Who said it returned specifically 1 or not 1. The results are zero and non-zero.
3. The 99999 should have been passed as another parameter to the function, or at the very least made a constant for the whole file.

You're doing something like this:

Code:

int x;
....
scanf("%d",x); /* WRONG */

You should be doing:

Code:

int x;
....
scanf("%d",&x); /* Right */

thanks for your fast reply and sharp eyes, I can't believe I skipped that while reading it 3 times. I thought that I was dealing with a char pointer instead. One of my really silly mistakes when looking at variables with the same type. An because of this, I fixed the number = NULL part. Man, I hate my noobishness for first made it a char type and treated as a char pointer for the rest of the program (not only in this function).

> projectmain.c:10: warning: "struct database_input" declared inside parameter list
Move the "struct database_input..." declaration above where you first attempt to use it

Code:

struct foo {
  int member;
};
void func ( struct foo *bar );

Not

Code:

void func ( struct foo *bar );  // this will draw that first warning
struct foo {
  int member;
};

To be honest, you need to read your C book some more.