ConcatFiles creates an io.Reader that reads from the provided files in order.

CopyReaderToTemporaryFile creates a temporary file with a given prefix, name and copies data from a reader into it.

GarbageCollectTemporaryFiles deletes the oldest files in a directory based on a given mask, leaving only 'n' newest files.

WriteTemporaryFile creates a temporary file with a given prefix, name and writes data into it.