Depends, what source are you using? How do you determine if one is gm?
basic layout would be like this though.
Code:
if(Client.AccountStatus == ADMIN_FLAG)
{
// Admin commands
}
if(Client.AccountStatus >= GM_FLAG)
{
// Add commands available only for GMs here
}
if(Client.AccountStatus >= NORMAL_FLAG)
{
// Normal player commands
}
Now ofcourse Client.AccountStatus would be replaced w/e code determines ones flag.