Problem with MYSQL

I am using the Mysql C api and the DevPack made for this. But when I am using this code, I always get an Illegal Operation message when running the program:

Code:

---

#include <windows.h>
#include <iostream>
#include <mysql/mysql.h>

using namespace std;

int main()
{
    char *host = "sql1.badblock.com";
    char *user = "theuser";
    char *pass = "thepassword";
    char *db = "thedb";
    MYSQL_RES *result;
    MYSQL *res;

    MYSQL *sock;
    sock = mysql_init(0);
    if (sock) cout << "sock handle ok!" << endl;
    else {
        cout << "sock handle failed!" << endl;
        return EXIT_FAILURE;
    }

    if (res=mysql_real_connect(sock, host, user, pass, db, 0, NULL, 0))
        cout << "connection ok!" << endl;
    else {
        cout << "connection failed!" << endl;
        return EXIT_FAILURE;
    }
   
    mysql_query(res,"SELECT address FROM music WHERE pass=euro8");
    cout<<"Query done!";
    result=mysql_store_result(res);
    cout<<"Store result done!";
MYSQL_FIELD *field;
cout<<"mysql field done!";

while(field = mysql_fetch_field(result))
{
cout<<"in while!";
    cout<<field;
}
cout<<"while done!";
cin.get();
    mysql_close(sock);

    return EXIT_SUCCESS;
}

---

So I added some couts to see how far the program got, before illegal operation message appears. The last cout displayed is mysql field done. Any ideas?

As a first step, add a << flush to each of your debug printing lines to make sure they are printed immediatly and not buffered and forgotten when your app crashes:

Example:

Code:

---

cout << "in while" << flush;

---

What gets printed when you cout the field pointer ? I don't know the API, but maybe

Code:

---

cout << field->name << flush;

---

is more appropriate.

If both doesn't help, your best bet is getting a debugger. Does Dec-Cpp have one ?

same results...

Debug reported:
An access violation (segmantation fault) raised in your program

Well I just tested your program I get a connection failed

because I dont use my correct username password and database

>>result=mysql_store_result(res);

Your not checking result for NULL.

>>SELECT address FROM music WHERE pass=euro8

Might that be "SELECT address FROM music WHERE pass='euro8'"

??

It doesnt help, still I get the illegal operation message

Quote:

---

Originally Posted by maxorator

It doesnt help, still I get the illegal operation message

---

Have you tried running you're query through the MySQL Query Browser?

Does it return the recordset you expect?

You also need to check the result of mysql_query to see if it is non zero.