I've been using the last four days to narrow in a strange problem in my
I have a multi-threaded webserver running on an embedded ppc405 module
running Linux (2.4.2x) and libgcj (3.4.3 - ancient I know). The
webserver is running SSL (thanks to Jessie) with keep-alive support. Fine!
However, due to a typo in my connecting SSL-client, I somehow forced the
client/server to create a new socket connection (and thereby start
SSL-handshaking) each time the client wanted to talk to the server.
(The "somehow" on the client, was registering a new HostnameVerifier and
a new SSLSocketFactory on HttpsURLConnection.)
This consequently made each thread belonging to an old request hang in a
"read()" way down in Jessie on a
However, as the sockets were "closed" (or whatever Sun's
HttpsURLConnection implementation does when "abandoning" its cached
sockets in my client) I would have expected the stuck invocations to
"read()" to return -1 more or less immediately afterwards. (As all the
faulty examples I've created to reproduce this does!)
But no, instead of returning, they just keep being stuck there - but not
After some 10-20 new connections to my server, _suddenly_ 10-20 stuck
read()'s "return" by throwing me IOException's with "Bad file descriptor"!
And now, I really don't care if I get "-1" returned cleanly or I am
thrown these IOException - that is, _if_ it didn't "brake" the new
socket connection triggering the throwing.
And for "brake" I have only a vague explanation:
1) Mostly I've seen "huge" amounts of data (~200 chars) disappear from
the triggering socket's inputstream. Resulting in my request-thread
getting stuck in a read() never getting any of the expected data.
2) On seldom occasions I've seen only "small" amount of characters
disappear - one char, and sometimes more.
That was a long story, but I have a smole hope that somebody can guide
me further in solving this.
Alternatively, I would really like to know how to provoke read() to
throw "Bad file descriptor" instead of -1, so that I might have a chance
reproducing this with a much smaller example.