Sorry for previous mail with no additional content, yahoo mail client is very sensitive apparently.
> On Saturday, 1 August 2015, 10:43, Philippe Gerum <r...@xenomai.org> wrote: >On 07/31/2015 07:54 PM, Frederik Bayart wrote: >>> On Thursday, 30 July 2015, 18:10, Philippe Gerum <r...@xenomai.org> wrote: >>> On 07/30/2015 05:08 PM, Frederik Bayart wrote: >>>>> On Thursday, 30 July 2015, 16:28, Frederik Bayart >>>>> <frederik_bay...@yahoo.co.uk> wrote: >>>>> >>>>> I found already that 'select' on socket(PF_UNIX, SOCK_STREAM, 0) causes >>>>> Interrupted system call (errno 4). >>>>> If I replace 'select' with '__real_select' the problem seems to be >>>>> solved, and the select timeout works. >>>>> But the select doesn't seem to react on connect. I'm looking at the >>>>> problem. >>>> >>>> >>>> I just notice that the flood of Interrupted system calls is only cause >>>> when build with trank. When build with alchemy, Interrupted system call >>>> just happens once. >>> >>> libtrank is just an overlay on top of libalchemy, only consisting of >>> fairly simple wrappers. I would suspect a difference in the flags passed >>> to xeno-config instead. >> >> I succeeded to start my server using alchemy directly. >> >> Via trank the program generates a flood of error: >> >> $ sudo ./ptest >> >> ptest.c:68 ERROR: select(4): Interrupted system call >> ptest.c:68 ERROR: select(4): Interrupted system call >> ptest.c:68 ERROR: select(4): Interrupted system call >> ... >> >> In attachment a test file ptest.c and makefile to reproduce the problem. >> >> My original server uses both native and posix calls, for that I used both >> native and posix flags. >> >> XENO_CFLAGS = $(shell $(XENOCONFIG) --posix --compat --native --cflags ) >> XENO_LDFLAGS = $(shell $(XENOCONFIG) --posix --compat --native --ldflags ) >> >> With alchemy directly there is no problem : >> >> XENO_CFLAGS = $(shell $(XENOCONFIG) --alchemy --cflags) >> XENO_LDFLAGS = $(shell $(XENOCONFIG) --alchemy --ldflags) >> >> >> I noticed also that for the documentation of the transition kit at the >> bottom >> http://xenomai.org/migrating-from-xenomai-2-x-to-3-x/#Using_the_Transition_Kit >> : >> >> If I link with xeno-config --posix --ldflags --compat, I get : >> >> cc -Wl,@/usr/lib/cobalt.wrappers -ltrank /usr/lib/xenomai/bootstrap.o >> -Wl,--wrap=main -Wl,--dynamic-list=/usr/lib/dynlist.ld -L/usr/lib -lcobalt >> -lpthread -lrt -lfuse -pthread -o ptest ptest.o >> /usr/lib/libtrank.so: undefined reference to `threadobj_set_schedparam' >> /usr/lib/libtrank.so: undefined reference to `__current_rt_alarm_create' >> /usr/lib/libtrank.so: undefined reference to `rt_task_self' >... >> /usr/lib/libtrank.so: undefined reference to `__current_rt_alarm_delete' >> /usr/lib/libtrank.so: undefined reference to `xnmalloc' >> collect2: error: ld returned 1 exit status >> makefile:27: recipe for target 'ptest' failed >> make: *** [ptest] Error 1 >> >> With the --native flag added, this is solved because -lalchemy >> -lcopperplate is then added. > >The issue is not between --alchemy and --native, but with --posix being >added or not. I could not reproduce this behavior (x86, ppc or arm) >using your exact test code (I can see timeouts triggering each 5s), but >looking at it, I'm pretty sure this is due to passing regular linux fds >(from socket(AF_UNIX) to RTDM services. > >When --posix is given, select(), socket() and friends will be routed to >RTDM _first_, which will check whether the corresponding channels are >connected to a real-time driver. If the fds are not managed by RTDM, the >call will be redirected to the glibc eventually. I don't explain why >your code receives EINTR from RTDM's select() yet, but this is most >likely not related to libtrank. This behavior is unexpected though, so >we have to find why Xenomai's select() behaves like this. If I can help, let me know, then I try to make some time to look at it. If you can't reproduce the problem, I could always run some test program on my PC. What is the best way to debug it ? Just to exclude : could it be an installation issue ? Have you xenomai installed in /usr/xenomai/... ? I'm using debian installation so that could be a difference. Any hardcoded library paths ? Frederik > >In the meantime, if you want to mix Xenomai/POSIX calls with regular >glibc ones when --posix is in effect, you can alternatively: > >- tag all regular POSIX calls for which a Xenomai counterpart exist with >__STD(call(args)) >- invoke __real_call(args) > >Alternatively, you can drop --posix which will disable the POSIX >wrapping for your code, then invoke __RT(call(args)) explicitly for >Xenomai real-time services. > >Philippe. _______________________________________________ Xenomai mailing list Xenomai@xenomai.org http://xenomai.org/mailman/listinfo/xenomai
