My client can not receive data in blocking mode

[Michael Wojcik]

From: openssl-users [mailto:openssl-users-bounces at openssl.org] On Behalf Of llf at e-code.net
Sent: Friday, September 27, 2019 11:42

> The data seems be cached on the server and not be sent out.

Is it? Have you run a network trace? Have you tried waiting longer than 100ms?

If your server is sending a segment shorter than the MSS, you may be seeing Nagle / Delayed ACK interaction. If that's holding up the end of a TLS record, then select will indicate the socket is readable but a subsequent SSL_read will block until the remainder of the record has been received.

A network trace, even without decryption, will give you some idea of when data is being sent, and how much.

--
Michael Wojcik
Distinguished Engineer, Micro Focus