[Rd] Problem using ofstream in C++ class in package for MacOS X

Ross Boylan ross at biostat.ucsf.edu
Thu Feb 8 21:32:45 CET 2007


On Sun, Feb 04, 2007 at 10:47:37PM +0100, cstrato wrote:
> Seth Falcon wrote:
> > cstrato <cstrato at aon.at> writes:
> >   
> >> Thank you for your fast answer.
> >> Sorrowly, I don´t know how to use a debugger on MacOS X, I am using 
> >> old-style print commands.
> >>     
> >
> > You should be able to use gdb on OS X (works for me, YMMV).  So you
> > could try:
> >
> >       R -d gdb
> >       run
> >       # source a script that causes crash
> >       # back in gdb, use backtrace, etc.
> >
> > + seth
> >
> >
> >   
> Dear Seth
> 
> Thank you for this tip, I just tried it and here is the result:
> 
> Welcome to MyClass
>  > writeFileCpp("myout_fileCpp.txt")
> [1] "outfile =  myout_fileCpp.txt"
> Writing file myout_fileCpp.txt using C++ style.
> ---MyClassA::MyClassA()---------
> ---MyClassA::WriteFileCpp---------
> 
> Program received signal EXC_BAD_ACCESS, Could not access memory.
> Reason: KERN_PROTECTION_FAILURE at address: 0x00000006
> 0x020fe231 in std::ostream::flush (this=0x214f178) at 
> /Builds/unix/o403/i686-apple-darwin8/libstdc++-v3/include/bits/ostream.tcc:395
> 395     
> /Builds/unix/o403/i686-apple-darwin8/libstdc++-v3/include/bits/ostream.tcc: 
> No such file or directory.
>         in 
> /Builds/unix/o403/i686-apple-darwin8/libstdc++-v3/include/bits/ostream.tcc
> (gdb)
> 
> It seems that it cannot find ostream.tcc, whatever this extension means.
> 
> Best regards
> Christian

I also don't see what the problem is, but have a couple of thoughts.
Under OS-X there is an environment variable you can define to get the
dynamic linker to load debug versions of libraries.  I can't remember
what it is, but maybe something like DYLD_DEBUG (but probably DEBUG is
part of the value of the variable).

For that, or the tracing above, to be fully informative you need to
have installed the appropriate debugging libraries and sources.

You may need to set an explicit source search path in gdb to pick up
the source files.

Try stepping through the code from write before the crash to determine
exactly where it runs into trouble.

Does the output file you are trying to create exist?

Unfortunately, none of this really gets at your core bug, but it might
help track it down.

Ross



More information about the R-devel mailing list