You're not supposed to address the general saying hi.
4 seconds sound clip from the Good Morning, Vietnam movie soundboard.
You can hear this line at 00:06:27 in the Blu-ray version of the movie.
Quote context
[...]
- I'm the tallest hog in the trough around here.
- Garlick, have you put on some weight?
- My son, the shadow of your ass would weigh 20 pounds.
- You're not supposed to address the general saying hi.
- That's Lieutenant Hauk in there.
- Who's the guy with the ears?
- You could fly to Guam with those.
[...]