Im new to c++ and I dont know what this error means. It reads from a file and tries to store the values in a char * [].
The file contains:
5,Justin,19,123-45-6789,State Farm,9876,Jessica,Broken Hand,
This is my code.
void Hospital::readRecordsFile(){
std::ifstream fileStream;
fileStream.open(fileName); // Opens the file stream to read fileName
char * temp [8];
int i = 0;
while(!fileStream.eof()){
fileStream.get(temp[i],256,',');
i++;
}
i = 0;
for(char * t:temp){
std::cout << t << std::endl;
}
}
The error is at the line fileStream.get(temp[i],256,',');
You define an array of 8 pointers to char, but forget to allocate memory so that the pointers point to a valid chunk of memory:
char * temp [8]; // need then to allocate memory for the pointers
Because of this, in the line
fileStream.get(temp[i],256,',')
you end up using memory that's not yours.
Solution:
for(int i = 0; i<8; i++)
temp[i] = new char[256]; // we allocate 256 bytes for each pointer
Better though, use a std::vector<std::string> instead.
In the code you have right now it looks like you implicitly assume that the file has no more than 8 lines, which I find hard to believe. If your file has more than 8 lines, then you'll end up accessing the array of 8 pointers out of bounds, so you'll get another undefined behaviour (usually a segfault). That's why is much better to use standard STL containers like std::vector, to avoid all these headaches.
In case you MUST use pointers and want a variable number of lines, then you have to use a pointer to pointer,
char** temp;
then allocate memory for an enough pointers-to-char,
temp = new char* [1000]; // we believe we won't have more than 1000 lines
then, for each pointer-to-char, allocate memory
for(int i = 0; i < 1000; ++i)
temp[i] = new char[256];
At the end of the program, you must then delete[] in reverse order
for(int i = 0; i < 1000; ++i)
delete[] temp[i];
delete[] temp;
As you can see, it's getting messy.