CharStr (PCH) - output
Address of the buffer where the character string is returned.
Length (PULONG) - in/out
Address of the buffer length in bytes.
Row (ULONG) - input
Starting row of the field to read, where 0 is the top row.
Column (ULONG) - input
Starting column of the field to read, where 0 is the leftmost column.
VioHandle (HVIO) - input
This must be 0, unless the caller is a Presentation Manager application; in this case, it must be the value returned by VioCreatePS.
rc (APIRET) - returns
VioReadCharStr returns one of the following values: