Runtime Error in using function call by reference?

Question

I have a class defined as,

class dimension{
public:
    dimension();
    const char* getname();
    long ing getlength();
    void setname(const char* text)
    void setlength(long int size)
    virtual ~dimension();
private:
    const char* name;
    long int length;
}

I am getting error regarding the functions setname and setlength are of importance so their definitions are as,

void dimension::setname(const char* text)
{
    dimension::name = text;
}
void dimension::setlength(long int size)
{
    dimension::length = size;    
}

Now i have 2 functions which i am using to read an array of objects of class dimension from a file. Their definition is as.

void read_dimension(dimension** dims, int*ndims, const char* text, long int size)
{
    int i;
    *dims = new dimension[*ndims];
    for(i=0; i<ndims; i++)
    {
        (*dims)[i].setname(text)   
        (*dims)[i].setlength(size) 
    }
}

void read_file(char *path, dimension** dims, int *ndims)
{
    //do-- open file and read the variables ndims, text and size from it.
    read_dimension(dims, ndims, text, size);
    //do-- print name and length of all elements of (*dims).
}

Now, i am calling these functions in main as

int main()
{
    //do-- get file path
    dimesnion* gdims;
    int num_dims;
    read_file(path, &gdims, &num_dims);
    //do-- print name and length of each element of gdims.
    return 0;
}

When i run the code the variable "name" printed from the the functions read_dimension() and main() are different but the variable "length" is the same.
I can't figure out why this is happening.
I would be glad if anyone could help.

Answer 1

There's no doubts text is a local variable in read_dimension function, probably an array of char. dimension::setname assigns one pointer to another, as already mentioned, what happens when text variable in read_dimension function goes out of scope? It'll die... Now your pointer in dimension class points to "nowhere". I prefer to use const char * as string literals or as pointer to some char in array of chars. If you want to store a string you'd copy it via strcpy maybe, of course destination array of char with sufficient space must exists.

What's the purpose of this code: dimension::name = text; and dimension::length = size; in setname and setlength methods? You're in the scope of dimension class, aren't you?