1. When precisely does a stream start? When a source is connected to its sink? When you call .run() on a top-block?
2. When adding stream tags to a stream, does the stream itself get altered? If I were to output the stream to a binary file, would the file look the same with and without stream tags?
3. If I have multiple USRPs receiving data at the same frequency and sampling rate, all outputting their streams to separate binary files, will sample n on binary file 0 be taken at the same time as sample n on binary files 1, 2 ... up to the number of USRPs, assuming all USRPs have been synchronized with the same clock and PPS signal?