It appears to work in Julia 0.4 - at least I hasn't crashed yet - but I have not really stress tested it.
Just disabling SIGINT only gets me half of the way. It will stop the function from crashing, but these calls may run for a long time, and in some cases it may be relevant to manually stop the call when a sufficiently good solution has been found. Is there any robust way to receive notification about ctrl-c or check if a ctrl-c has happened before returning from a native function? On Friday, June 3, 2016 at 5:24:28 PM UTC+2, Yichao Yu wrote: > > On Fri, Jun 3, 2016 at 4:51 AM, Ulf Worsoe <ulf.w...@mosek.com > <javascript:>> wrote: > > I am developing Mosek.jl. > > > > That library works by creating a task object, adding data to it and > calling > > a solve function. When a user in interactive mode hits ctrl-c, calls to > > native functions are terminated, and that leaves the task object in an > > inconsistent state, meaning that even calling the destructor may cause > it to > > segfault. This is why I am trying to take over the ctrl-c signal. I do > > something like this > > ( > https://github.com/JuliaOpt/Mosek.jl/blob/sigint/src/msk8_functions.jl#L2291-L2308): > > > > msk_global_break = false > > function msk_global_sigint_handler(sig::Int32) > > println("msk_global_sigint_handler") > > global msk_global_break = true > > nothing > > end > > > > function optimize(task_:: MSKtask) > > trmcode_ = Array(Int32,(1,)) > > SIGINT=2 > > old_sighandler = > > > ccall((:signal,"libc"),Ptr{Void},(Cint,Ptr{Void}),SIGINT,cfunction(msk_global_sigint_handler, > > > > Void, (Cint,))) > > res = @msk_ccall( > > "optimizetrm",Int32,(Ptr{Void},Ptr{Int32}),task_.task,trmcode_) > > ccall((:signal,"libc"),Void,(Cint,Ptr{Void}),SIGINT,old_sighandler) > > global msk_global_break > > if msk_global_break > > global msk_global_break = false > > throw(InterruptException()) > > end > > > > if res != MSK_RES_OK > > msg = getlasterror(task_) > > throw(MosekError(res,msg)) > > end > > (convert(Int32,trmcode_[1])) > > end > > > > During long calls the msk_global_break flag is checked, and if set, the > > operation terminates in a controlled manner. > > This will not work on 0.5 at least, not sure about 0.4. > SIGINT is blocked on all threads and there are always more then one > threads, one of them unmanaged and can't run any julia code. > You should be able to just use `disable_sigint` to do this on both 0.4 > and 0.5. It is not necessary on 0.5 if the ccall doesn't call back to > julia. > > > > > I have seen older answers to similar questions, saying that this could > cause > > problems, but have been told that threading may be handled different > now. Is > > this something I can expect to work in Julia 0.4 and/or 0.5? In > particular, > > if the native optimizetrm function creates multiple threads, will this > still > > work? >
