Newby - how to observer changes in FIFO pipe

andsun

Hi all,

I'm trying to learn Linux coding in Qt c++.

At the moment I'm struggling with my GUI.
I have an application (as a controller in the system) connected to some instruments that sends update info to my gui through a FIFO pipe. Is there a way to, within an observer class watch the FIFO for changes, signal to my reader to read the pipe?

The update data doesn't come regulary rather that now and then between 1 -25 seconds apart.

/anders

Francknos

What type of data contain your FIFO ? int double ? string structures ?

andsun

Hi, its a struct that is sent trough the pipe, usually.

Francknos

You know the content of this structure ?
Do you have more information about your problem.

tomasz3dk

I think, that solution for this will be a "QSocketNotifier":http://doc.qt.io/qt-5/qsocketnotifier.html, and it's activated signal.

andsun

Hi all, I found a solution for my problem. Using inotify does the trick.
Found help here:
http://www.thegeekstuff.com/2010/04/inotify-c-program-example/

The glitch I see now is QFileDialog that doesn't show hidden files/folders, however hardcoding the hidden name and passing it to inotify works

This can be closed now, from my point of veiw