Clarify that the value of getc() etc. is an unsigned char converted to an int (as per the C standard) i.e. it can be passed straight to isalpha() etc.
Clarify that the value of getc() etc. is an unsigned char converted
to an int (as per the C standard) i.e. it can be passed straight to
isalpha() etc.

Approved by:	dwmalone (mentor)
MFC after:	3 days

jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase