Hello
This is just a function prototype for a function that can be called by printf to write output to stdout as a whole string.
Idea here is that printf is ready to support that as soon as a programmer implements such a function.
As stated in my previous email the fact that you want to send the whole string at once is probably a requirement from the device you want to use for stdout.
So you need to write the driver for that device.
The SCI we are using as stdout in TermIO.c can only transfer one character at a time. So there is no reason for implementing a PutString function there.
CrasyCat