gksu with c++
 

Hi...

how can I use gksu command in my qt program to make it run under root user ???

do you want to start your program as root ? or do you want to start another application from within your program as root ?
In the first case, just do 'gksu yourprogram', in the second case I wouldn't use (gk)su at all.
Instead create a little setuid root wrapper executable, which calls the program.