Re: Tcl8.5/Tclx8.4 fork doesn't work properly



As I expected, tcl 8.4 with threads support doesn't work properly with fork.
Child process is waiting for something.
strace -p <pid> shows the following
[dan@king BIND]$ strace -p 4849
Process 4849 attached - interrupt to quit
futex(0x8f4a8c4, FUTEX_WAIT, 3, NULL <unfinished ...>
Process 4849 detached

Seems like there is a bug. Who should take a look at this issue ? Somebody
from tcl core devs ?

On Jan 1, 7:54 pm, "Daniel A. Mezentsev" <dmezent...@xxxxxxxxxxx>
wrote:
Alexandre Ferrieux wrote:
On Jan 1, 7:26 pm, "Daniel A. Mezentsev" <dmezent...@xxxxxxxxxxx>
wrote:
Hi folks,
I've updated my tcl installation 8.4-->8.5, not everything (tclx still
8.4) and my project stopped to work. I did some investigation and
found that there are some problems with fork. Here is example of code
which work just fine under tcl8.4 (without thread support) and doesn't
work under 8.5 (with thread support):

Why use a threaded version under unix ? Threads and fork don't make a
happy blend.

-Alex

I know that threads + fork potentially can cause problems (seems like I
hit one of them). Is there workaround to solve this problem and use 8.5
with threads support or I should recompile tcl with threads disabled.
Apparently this problem wider - why binary distribution has so obvious
bug (or feature ;-)).

Sure, but keeping orthogonal things orthogonal is a nice habit. Here
you changed simultaneously the version and the thread support... So
did you try with 8.4-threads ?

-Alex

.



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