/ dev / urandom maximum size

Question

If you want to read N bytes guaranteed with / dev / urandom, is it safe to make one read call and guarantee that you will receive N bytes - or are there some operating systems that do not provide this guarantee and can do a short read from / dev / urandom?

Answer 1

Reading from /dev/urandommay return to full satisfaction if interrupted by a signal.

Answer 2

, , , , , . , - , /dev/urandom .