Targeting OS 3.0 with the OS 3.1 SDK

[JB Parrett]

I'd like to use the newest SDK to compile apps that still run under 
OS 2.0 or 3.0, but I'm running into problems. Specifically, if I use 
statements like

   if (IsPrint(GetCharAttr(), pEvent->data.keyDown.chr))
      HandleKey(pEvent->data.keyDown.chr);

the compiler complains that I should be using TxtIsPrint(ch)

or if I write my own comparison routine and use

   pTable = GetCharCaselessValue();

I am told to use TxtCaselessCompare().

I only get the option to use the new Text Manager calls, which are 
only available for >= OS 3.1. Do I have to build special pre-compiled 
headers to take out the Text Manager stuff in order to get a build?

JB