What does the sentry command do?

[drtachyon]

I've looked in all of the rule books and on this website, but I cannot find a description of the sentry command. Sorry if this is obvious, but I can't tell the difference between this and the fortify command.

Thanks.

Dr. Tachyon

 

[Strider]

The sentry command makes a unit fortify and then un-fortify when a enemy units comes close.

 

[Sparrow3]

Fortify - Unit only wakes up if attacked. Defends and then immediately refortifies.

Sentry - Unit wakes up if foreign unit comes within one tile of him. Remaims awake unitl you re-sentry the unit. Unit that awakens sentry does not have to be at war with sentry's Civ.

 

[globester]

doesn't fortify give a defensive bonus as well?

and if you played civ2, sentry is just like sleep, cept it doesn't load your units