Thread: MySQL C Api

Hi! I have the following source code which seems to compile fine without any errors, however when I try to execute the binary, I get a core dump. The strace output doesn't lead me to think of any foul play.. so I wonder what can be wrong and hence this post directed to you experts

Code:

root@chris-desktop:~# gcc my.c -o my -L/usr/mysql/lib -lmysqlclient -lz -ldl
root@chris-desktop:~#

root@chris-desktop:~# ./my
Segmentation fault (core dumped)
root@chris-desktop:~#

I have reason to believe the error lies in the sprintf function I am using... however I dont quite see why ? Any help would be most appreciated. Kind regrards, Chris

Code:

#include <stdio.h>
#include <mysql/mysql.h>
#include <pwd.h>

int main (int argc, char **argv) { 


      MYSQL  *conn;                  

      conn = mysql_init (NULL);
      struct passwd *pwd_ent;




     #define def_host_name  "localhost" /* host to connect to  */
     #define def_user_name  "root"      /* user name  */
     #define def_password   ""          /* password  */
     #define def_db_name    "history"   /* database to use  */


	if (mysql_real_connect (

        	conn,          /* pointer to connection handler */

        	def_host_name, /* host to connect to */

        	def_user_name, /* user name */

        	def_password,  /* password */

        	def_db_name,   /* database to use */

        	0,             /* port (use default) */

        	NULL,          /* socket (use default) */

        	0)             /* flags (none) */

      == NULL)

  	

	{

    		fprintf (stderr, "mysql_real_connect() failed:\nError %u (%s)\n",

                mysql_errno (conn), mysql_error (conn));

  	}







      char query[1000];

      sprintf(query,"insert into history values('',curdate(),curtime(),'%d','%d','%s','%s')",pwd_ent->pw_uid,pwd_ent->pw_gid,pwd_ent->pw_name,"");



     

        



      /* End  Modifications */ 

}

Thanks for your replies, still no luck even if I do escape all ' i.e.

Code:

sprintf(query,"insert into history values(\'\',curdate(),curtime(),\'%d\',\'%d\',\'%s\',\'%d\'\) ",pwd_ent->pw_uid,pwd_ent->pw_gid,pwd_ent->pw_name,pwd_ent->pw_gid);

debugging:

root@chris-desktop:~# gcc a.c -o a -L/usr/lib/mysql/ -lmysqlclient -lz -ldl -g
root@chris-desktop:~# ./a
Segmentation fault (core dumped)
root@chris-desktop:~#

gdb output:

#0 0x0804867b in main (argc=1, argv=0xbfd48634) at a.c:60
60 sprintf(query,"insert into history values (\'\',curdate(),curtime(),\'%d\',\'%d\',\'%s\',\'% d\') ",pwd_ent->pw_uid,pwd_ent->pw_gid,pwd_ent->pw_name,pwd_ent->pw_gid);
(gdb)

wow!! Mr. Salem here is so smart.. i've read some of the FAQ's and most of the codes were written by you.. hehehe! =D