[BRLTTY] dlsym/dlerror (was Re: Clumping all the braille driver modules into one big app?)

[Dave Mielke]

[quoted lines by Willie Walker on 2008/08/29 at 11:50 -0400]

>The _ex_unwind thing happens somewhere way prior to the call to dlsym. 

Which is what makes it rather strange. Maybe the code is assuming that 
dlerror() is always called by the application, i.e. maybe it can't handle 
tracking two errors at once.

>I'm not sure of the exact time or why it is referenced -- I can try to 
>find the exact specifics if you really need them, but I believe it has 
>something to do with cleaning up threads when they exit.  It is not 
>referenced as a part of the call to dlsym.

I just don't like claiming that a problem has been fixed when it isn't 
understood.

>In any case, yes, I tested the code before and after the one line 
>change.  It fails before and works after.  :-)

Okay. The new code, as now committed to the development stream, is exactly the 
same as the old code except that dlerror() is additionally called just before 
the call to dlsym().

>PS - I've asked the folks responsible for the _ex_unwind thing to clean 
>up the dlerror state if they caused it to come into being.  While what 
>they are doing is probably OK, the resulting error is confusing and 
>unexpected.

Thanks.

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