I'm writing embedded code for STM32F3 mc (STM32F3-Discovery). I need to output some data to UART and I'm using DMA for this as this allows me to concentrate on sensors reading and data processing rather than on waiting for byte transmission completion. The issue however is that I have to combine:

1. Formatted output (i.e. some from of printf)
2. A number of consecutive prints (that occur before previous print has finished)

So I'm thinking about a circular buffer. But I don't think I know how to make sprintf to respect the end of buffer and continue writing to the beginning of the buffer. I can of course create another temporary buffer, print there, and copy byte-by-byte, but it doesn't look elegant to me.