Beefy Boxes and Bandwidth Generously Provided by pair Networks
Keep It Simple, Stupid
 
PerlMonks  

Re^2: Signals vs. Windows

by DanEllison (Beadle)
on Oct 03, 2012 at 17:33 UTC ( #997107=note: print w/replies, xml ) Need Help??


in reply to Re: Signals vs. Windows
in thread Signals vs. Windows

The pertinent text I missed was actually out of "threads" which was:

Correspondingly, sending a signal to a thread does not disrupt the operation the thread is currently working on: The signal will be acted upon after the current operation has completed. For instance, if the thread is stuck on an I/O call, sending it a signal will not cause the I/O call to be interrupted such that the signal is acted up immediately.

Nothing in the documentation suggests that signals are not the way to perform IPC, but simply threads don't react to signals as well as processes. Keep in mind, I don't want to simply suspend or terminate the thread, but interrupt it and send it off in another direction. So, the problem restated is, I guess, how do I interrupt a thread from an I/O operation?

Replies are listed 'Best First'.
Re^3: Signals vs. Windows
by bulk88 (Priest) on Oct 03, 2012 at 19:48 UTC
    So, the problem restated is, I guess, how do I interrupt a thread from an I/O operation?

    1. dont use blocking I/O, use overlapped/async I/O

    2. use Native API, create an alertable *synchronous* file handle using NtCreateFile, post a timer APC to the blocked thread with SetWaitableTimer, the APC will call CancelIo from within the blocked thread, and the blocked I/O will unblock.
      I'm trying to avoid a Windows only solution.
Re^3: Signals vs. Windows
by Anonymous Monk on Oct 03, 2012 at 17:49 UTC

    Nothing in the documentation suggests that signals are not the way to perform IPC

    Hmm, "unsafe" about says it all :)

    So, the problem restated is, I guess, how do I interrupt a thread from an I/O operation?

    stop using safe signals, use unsafe signals, use kill

Log In?
Username:
Password:

What's my password?
Create A New User
Node Status?
node history
Node Type: note [id://997107]
help
Chatterbox?
[marto]: xubuntu or lubuntu
[Corion]: :-D
[marto]: my desktop is a core2 duo, 120GB SSD, 4GB RAM, boots to (GUI) login in less than 10 seconds from cold start
[Discipulus]: mah, winbuntu 10...
[marto]: whent he boys start school I'll build myself as new machine, ryzen based
[Corion]: marto: That's cool! I think my (home) desktop spends 30 seconds in the BIOS...
[Corion]: marto: Heh - currently they seem promising, but I think I'll stay with nVidia+Intel for the time being, as I've been bitten too often by bad AMD drivers
Discipulus is (still?) not a big fan of notepad++
[marto]: Corion, I think in the past this was a big problem for them. GPU driver wise the improve all the time. I use the open source drivers on my machine (old R9 270, 2GB) and had no problems

How do I use this? | Other CB clients
Other Users?
Others scrutinizing the Monastery: (7)
As of 2017-07-27 08:56 GMT
Sections?
Information?
Find Nodes?
Leftovers?
    Voting Booth?
    I came, I saw, I ...
























    Results (407 votes). Check out past polls.