hzhijun wrote:
> i don't think it need to set locking_function since i did not use any shared datastructures in my application.
you may not, but the OpenSSL-LIB does definitly. And as soon as your
application gets multithreaded, you always risk a race conditions which
not neccessarily could cause a crash, but which could.

Although OpenSSL uses many global data structures, all i have to do is
use the proper compiler to build OpenSSL with multithread options.
...for having it built with multithread-supprt this is sufficient, but
as soon as you know your application gets multithreaded (whether you
spawn threads by your own or you use some library-functions which does
this for you (implicitly)...for example using the multi-interface from
libcurl should be enough) it is a must to "give" the OpenSSL-Lib the
callbacks to be able to lock their global datastructures, nevertheless
your app would work without the locks very often or even nearly always,
it is not relieable and not a good way to code. You probably/hopefully
would use locking mechanism to protect data-access to your global
datastrucutres if you would had some in *your* multithreaded
application. Just because you dont't see the library's code which spawns
threads and makes accesses to global data from this threads, it ist no
good idea not to lock the accesses. You just risk having the whole
application crashed in some day. And in this day you even might have
forgotten about the locking issue, so I predict you wont' find the cause
or even some indicators for it.

Anyway, best wishes. If you need some help on how to provide those
callbacks in a propriate way, just let know.

Ciao, Frank.
Received on 2004-11-16