OpenSSL::Buffering#fill_rbuff

# File tmp/rubies/ruby-4.0.0/ext/openssl/lib/openssl/buffering.rb, line 74
def fill_rbuff
  begin
    @rbuffer.append_as_bytes(self.sysread(BLOCK_SIZE))
  rescue Errno::EAGAIN
    retry
  rescue EOFError
    @eof = true
  end
end