Последовательный порт открыт в raw режиме, а в man 2 read написано что «zero indicates end of file», а прерывание из-за полученного сигнала возвращает -1. Стоит ли делать лишнюю (или не лишнюю) проверку на 0?
P.S. man:
RETURN VALUE
On success, the number of bytes read is returned (zero indicates end of file), and the file position is advanced by this number. It is not an error if this number is smaller than the number of bytes requested; this may happen for example because fewer bytes are actually available right now (maybe because we were close to end-of-file, or because we are reading from a pipe, or from a terminal), or because read() was interrupted by a signal. On error, -1 is returned, and errno is set appropriately. In this case it is left unspecified whether the file position (if any) changes.
