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Qt application on raspberry pi with read only raspbian jessie

  • Hi all,

    I developed a QML application which is basically a dummy application to be used on read-only file system because I want to prolong micro SD card's life and avoid memory corruption in case of power loss. The application simply receives messages and images over UDP sockets, and shows them on the screen. The problem I have is that when I am in read-only mode application just aborts after about half a second or so. When it is run in read-write mode it works great.

    After removing chunks of code and testing it in read-only mode I found out that if application don't process received UDP datagrams, which i really have to since that's the only functionality application has, it doesn't get aborted. I am not that good with Linux to be honest, but what seems logical to me is that when I read that data in application it needs to be stored somewhere, and that somewhere is in read-only part of memory.

    Does what I wrote make any sense? If yes which parts of file system need to be mounted as tmpfs to fix it? If not what is actually happening and is it possible to fix it somehow?

    At the moment I mounted /tmp, /var/log and /var/tmp as tmpfs.

    Thanks in advance.

  • Lifetime Qt Champion

    Hi and welcome to devnet,

    What are you doing in the processing part ?