segment fault in function

[dole_4]

hi,

I have some code that compiles 100% error/warning free, but whenever i execute the program its spits back segment faults.

The aim of the code is to search a 2d array (size rowXcol) for a specific character (in the first case 'W') and print to a file a string ("wumpus") plus the x/y co ordinates of where it occurs. Each time it occurs it should print the same string and different x/y co ords on a newline (FILE * passed down 1 line).
Then it should return the FILE * to the calling function where it can search for a new char , then print another string/x/y into the file and so on...


here is the code:
somewhere in int main() {
...
FILE* outFilePtr;

outFilePtr = insert_data( outFilePtr, 'W' , "wumpus", map, data );
outFilePtr = insert_data(outFilePtr, 'G' , "gold", map, data);
outFilePtr = insert_data(outFilePtr, 'P' , "pit", map, data);
outFilePtr = insert_data(outFilePtr, 'E' , "exit", map, data);
... }
FILE * insert_data( FILE * filePtr, char toFind, char word[], char ** map, int * data)
{
int c=0, d=0;
char line[25];
int row = data[5];
int col = data[6];


while( c < col ) {
while ( d < row ) {
if( map[c][d] == toFind ) {
sprintf( line,"%s %d %d\n", word , d, c);
fputs(line, filePtr);
}
d++;
}
d=0;
c++;
}
return filePtr;
}




Now i know the segment error occurs the first time it calls insert_data, but i can't find where. Possible its some error where a < is put in place of a > or something similar, but whatever it is, any help would be really appreciated.

Thanks.

[maes]

It actualy works for me. I changed nothing of your insert_data function and it works.
I did guess on what to put in the data and map array, but this was my output:
gold 1 1
pit 0 3
exit 4 0
Could this be right? there was no 'W' in my map array. I filled it from 'A' to 'T'. So that explains why wumpus isn't in the file

Here is the complete code I used to test it:

#include <stdio.h>

FILE * insert_data( FILE * filePtr, char toFind, char word[], char **map, int * data) ;


int main()
{
FILE* outFilePtr;
int data[]={0,0,0,0,0,0,0};//initialize data with 0
char **map;
int i,j;
int num_rows=4;//the max rows for the map array
int num_cols=5;//the max cols for the map array

map = new char*[num_rows];//allocata memory for the rows
for ( i = 0 ; i < num_rows; i++ ) map[i] = new char[num_cols];//allocate memory for the cols

for(i=0;i<4;i++)
{
for(j=0;j<5;j++)
{
map[i][j]='A'+((i*5)+j);//fill the map array with the first 20 chars of the alfabet
printf("%c",map[i][j]);//display them on screen
}
printf("\n");
}

data[6]=num_rows;//I have no idea what the data array should be holding
data[5]=num_cols;//I assume it is info on the map array, like max rows and max cols
outFilePtr=fopen("test.txt","w+");//open the file test.txt for the output of the insert_data function

outFilePtr = insert_data( outFilePtr, 'W' , "wumpus", map, data );
outFilePtr = insert_data(outFilePtr, 'G' , "gold", map, data);
outFilePtr = insert_data(outFilePtr, 'P' , "pit", map, data);
outFilePtr = insert_data(outFilePtr, 'E' , "exit", map, data);

for ( i = 0 ; i < num_rows ; i++ ) delete map[i];//remove the map array from memory
delete map;

fclose(outFilePtr);//close the test.txt file

return 0;
}



//Haven't changed anything here
FILE * insert_data( FILE * filePtr, char toFind, char word[], char ** map, int * data)
{
int c=0, d=0;
char line[25];
int row = data[5];
int col = data[6];

while( c < col ) {
while ( d < row ) {
if( map[c][d] == toFind ) {
sprintf( line,"%s %d %d\n", word , d, c);
fputs(line, filePtr);
}
d++;
}
d=0;
c++;
}

return filePtr;
}

[dole_4]

hmmm i should have really said this, but as I'm just learning C now, i don't know much about C++ (as i see you used new/delete and im not sure what they do, maybe malloc and free?).
I dont know if that makes a difference but anyway...


i have found out that the error is in the if statement in insert_data, (when i /* */ quote it out it runs fine), so can anyone see a problem with anything inside the if statement?


oh and on a bit of a different note, how do u make that 'code' quote with the 2 separators show up in your msg?

thanks

[maes]

yeah new and delete are the equivalent (sp?) of malloc() and free()

Personaly, I can't see anything wrong with your if statement. but then again, I'm no C/C++ guru.
Are you sure you allocate the memory for your map array right?
Because when you go out of the scope of your array, that can give errors

>>oh and on a bit of a different note, how do u make that 'code' quote with the 2 separators show up in your msg?
It is the same as the quote tags, but you put them between and

[dole_4]

thanks for the help


but the problem was in my main function,

for some reason i 'free' 'd the 2d array before i had finished using it.

but problem solved now.

thanks