[mindwaves]

I get that error when running a C++ program using PB. Thanks a lot.

[smeger]

Segmentation violation. It means your code tried to read or write from memory it didn't own (as in, memory it allocated for its own use).

Usually, this occurs when you read or write from an invalid pointer.

[yeslekmc]

I've also received this error from errant pointers, but the problem wasn't caused by the pointers being incorrectly assigned. The problem dwelled within a character array that was declared before the pointer variables. I read data (from an annex serial port) that was longer than expected and it over-wrote the bounds of my character array and spilled over into my pointer variables, thus corrupting them. The bottom line is, don't just look at all of the operations involving your pointer variables for the problem may be caused elsewhere...

[mindwaves]

Hey, thanks, but does anyone know where I can find an explanation of all these types of errors?

[Chuckit]

Originally posted by mindwaves:
Hey, thanks, but does anyone know where I can find an explanation of all these types of errors?

You can find a basic explanation in the signal manpage. It lists the signals, the default action they cause, and a short description (e.g. "bus error," "segmentation violation") of what they mean. If you want something more in-depth, you could probably google something on them.

[mindwaves]

Originally posted by Chuckit:

You can find a basic explanation in the signal manpage. It lists the signals, the default action they cause, and a short description (e.g. "bus error," "segmentation violation") of what they mean. If you want something more in-depth, you could probably google something on them.

Thanks.

[zanyterp]

Originally posted by smeger:
Segmentation violation. It means your code tried to read or write from memory it didn't own (as in, memory it allocated for its own use).

Usually, this occurs when you read or write from an invalid pointer.

is it then trial-and-error to find out how to fix it? i just ran across this error and instead of posting a new thread with the same topic, thought i would ask about one that already talked about it. . .but i am not seeing how to fix it. thanks!!

nick

[Ghoser777]

What always bugged me about how errors are dealt with in Objective-C versus Java is in Java, I would get a nice stack trace automatically and I could track down the error pretty easily. My guess is the only way to deal with these types of errors in Objective-C is to use gdb, which I've never gotten around to learning yet.

[Catfish_Man]

Originally posted by Ghoser777:
What always bugged me about how errors are dealt with in Objective-C versus Java is in Java, I would get a nice stack trace automatically and I could track down the error pretty easily. My guess is the only way to deal with these types of errors in Objective-C is to use gdb, which I've never gotten around to learning yet.

Xcode has a reasonably nice front end to GDB, which is quite easy to use. I find setting a breakpoint on [NSException raise] is handy.

[Thinine]

Hillegass recommends as much in his book.

And holy zombie thread Batman! I think it would have been okay to create a new thread, instead of bumping this ancient one.

[Kristoff]

"Most signals only go to ten. But this signal goes to eleven."

[Wevah]

Originally posted by Ghoser777:
What always bugged me about how errors are dealt with in Objective-C versus Java is in Java, I would get a nice stack trace automatically and I could track down the error pretty easily. My guess is the only way to deal with these types of errors in Objective-C is to use gdb, which I've never gotten around to learning yet.

CrashReporter not good enough for you?

[zanyterp]

Originally posted by Thinine:
Hillegass recommends as much in his book.

And holy zombie thread Batman! I think it would have been okay to create a new thread, instead of bumping this ancient one.

oops. guess i misunderstood how it was supposed to work with looking at previous messages . . . so to fix it (signal 11 error) just guess & check?

[Chuckit]

Originally posted by zanyterp:
oops. guess i misunderstood how it was supposed to work with looking at previous messages . . .

It's no biggie. There aren't really hard-and-fast rules for bumping threads (to my knowledge!). It's just a little jarring to see a post and realize it's something you said almost 3 years ago.

Originally posted by zanyterp:
so to fix it (signal 11 error) just guess & check?

Pretty much.

[zanyterp]

Originally posted by Chuckit:
It's no biggie. There aren't really hard-and-fast rules for bumping threads (to my knowledge!). It's just a little jarring to see a post and realize it's something you said almost 3 years ago.


Pretty much.

i can see how that would be rather jarring. i will keep that little scope in mind. and thanks for the answer.

nick