I have a program that tries to create three TLS connections at approximately the same time each from separate thread. Each thread is using a GSocketClient.

The result is that it always seem to fail for two of the connections (sometimes only one) while one of them works (almost always the first one). It fails with this error

 Proxy protocol 'http' is not supported. (g-io-error-quark, 15)

I captured a stack trace when it fails, see [1].

I wondered why it was trying to use a HTTP proxy and then I realized that it could be because I have my proxy settings set to

 Mode: Automatic
 Configuration URL: http://wpad/wpad.dat

If I disable the HTTP proxy then things work just fine.

As you can see, each socket client is trying to connect to

 host_and_port=0x638530 "imap.gmail.com"
 default_port=993

and I've also set the GSocketClient:tls property to TRUE. See

 http://cgit.freedesktop.org/~david/goa/tree/src/goabackend/goaimapclient.c#n217

for the actual code in question.

So this must be a bug with how proxying is handled.

Thoughts?

[1] :

(gdb) thread
[Current thread is 5 (Thread 0x7ffff5b03700 (LWP 24667))]
(gdb) print protocol 
$1 = (const gchar *) 0x7fffe00047a0 "http"
 

+ Trace 227163