PE> I have an application that writes a byte-at-a-time to the comm
 PE> port.  This works fine under DOS, but under OS/2 it requires an
 PE> OS call, which is not fine at all!!!  What is the simplest way
 PE> to overcome this problem

Simply put, write more than one byte at a time.  There are a number of
ways to accomplish that, including emulating standard C stream calls and
behaviors, and an abundance of freely available source.

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