What is a segmentation fault?

[24c]

Ok, for my sins, I tried MegaTunix today, and it worked on the MacBook, but still not got serial comms with the iMac. After some more snooping with the MacBook, I wanted to rework the gauges, mainly to suit my motorcycle engine limits, and see if I could create a neat dash.
I tried to open dashdesigner, and it gives me a segmentation fault on both machines, and unexpected quitting/error reports to Apple dialogs.

I've seen the woza thread of the same name, but does anybody know what this means in plain English?

[jsmcortina]

Try http://en.wikipedia.org/wiki/Segmentation_fault

It is a code bug basically, that caused an attempt to read or write some area of memory that is illegal.

A somewhat basic example might be this. Say you call a function that is supposed to return an address of a warning message. Next you print the message from that address. However, the function returns 0 or "NULL" instead of an address. Correct code will notice and think "oh, I got NULL, there isn't a message".
Buggy code won't check for errors and will try to use the bogus address anyway, that will either cause garbage or a segfault.

That kind of thing anyway.

James

[djandruczyk]

Ok, for my sins, I tried MegaTunix today, and it worked on the MacBook, but still not got serial comms with the iMac. After some more snooping with the MacBook, I wanted to rework the gauges, mainly to suit my motorcycle engine limits, and see if I could create a neat dash.
I tried to open dashdesigner, and it gives me a segmentation fault on both machines, and unexpected quitting/error reports to Apple dialogs.

I've seen the woza thread of the same name, but does anybody know what this means in plain English?

A segmentation fault is typically when a program tries to dereference a NULL pointer. i.e. a location to nowhere. that's at leat one of the potential (loose) definitions of a segfault. There was a very very subtle bug in the dashdesigner/gaugedesigner up till about 2 hours ago, which i have since committed.

I also fixed the dash/gauge designers to work on Ubuntu 8.04 again.

[24c]

...I also fixed the dash/gauge designers to work on Ubuntu 8.04 again.

So how do I update my MegaTunix file? Remove the old version and use git tree again, and the modular_0.4 branch, or can I self update?

[djandruczyk]

...I also fixed the dash/gauge designers to work on Ubuntu 8.04 again.

So how do I update my MegaTunix file? Remove the old version and use git tree again, and the modular_0.4 branch, or can I self update?

In your tree (i.e. /home/<username>git/Megatunix or similar) run the following

Code: Select all

sudo rm -rf /usr/local/share/MegaTunix
git checkout modular_0.4
./autogen.sh
make
sudo make install

[djandruczyk]

dashdesigner and hopefully gaugedesigner should now be more stable. Please test and report back.