PS: My current attempt to return a char** from the vector<string> looks
like this:
I'm converting to a vector<const char*>, then returning the address of the
first element.
const char* convert(const std::string& s)
{
return s.c_str();
}
const char** lcevtgetcollectionnames( void* event ){
LCEventImpl* evt = static_cast<LCEventImpl*>(event);
const std::vector<std::string>* nameVec = evt->getCollectionNames();
std::vector<const char*>* names = new std::vector<const char*>;
std::transform(nameVec->begin(), nameVec->end(),
std::back_inserter(*names), convert);
return &(*names)[0];
}
On the Julia side I'm trying this signature:
ccall((:lcevtgetcollectionnames, "test.dylib"), Ptr{Cstring}, (Ptr{Void},),
event)
But this results in a seg fault
signal (11): Segmentation fault: 11
lcevtgetcollectionnames at /Users/stru821/Workdir/Julia/test.dylib (unknown
line)
anonymous at no file:7
jl_apply at
/Users/vagrant/buildbot/slave/package_osx10_9/build/src/./julia.h:1299
jl_parse_eval_all at
/Users/vagrant/buildbot/slave/package_osx10_9/build/src/toplevel.c:573
jl_load at
/Users/vagrant/buildbot/slave/package_osx10_9/build/src/toplevel.c:616
include at
/Applications/Julia-0.4.0-dev-539c818c4e.app/Contents/Resources/julia/lib/julia/sys.dylib
(unknown line)
jl_apply at
/Users/vagrant/buildbot/slave/package_osx10_9/build/src/./julia.h:1299
include_from_node1 at loading.jl:133
jl_apply at
/Users/vagrant/buildbot/slave/package_osx10_9/build/src/gf.c:1632
process_options at
/Applications/Julia-0.4.0-dev-539c818c4e.app/Contents/Resources/julia/lib/julia/sys.dylib
(unknown line)
_start at
/Applications/Julia-0.4.0-dev-539c818c4e.app/Contents/Resources/julia/lib/julia/sys.dylib
(unknown line)
jlcall__start_18703 at
/Applications/Julia-0.4.0-dev-539c818c4e.app/Contents/Resources/julia/lib/julia/sys.dylib
(unknown line)
jl_apply at
/Users/vagrant/buildbot/slave/package_osx10_9/build/src/./julia.h:1299
true_main at
/Applications/Julia-0.4.0-dev-539c818c4e.app/Contents/Resources/julia/bin/julia
(unknown line)
main at
/Applications/Julia-0.4.0-dev-539c818c4e.app/Contents/Resources/julia/bin/julia
(unknown line)
Segmentation fault: 11
On Sunday, June 14, 2015 at 2:43:24 PM UTC+9, Jan Strube wrote:
>
> Hi,
>
> I'm trying to wrap the LCIO file format http://lcio.desy.de/ in Julia.
> I have a proof of principle working and am starting to add more of the API.
>
> What totally stumps me is this signature:
> virtual const std::vector< std::string > *
> getCollectionNames
> <http://lcio.desy.de/v02-04-03/doc/doxygen_api/html/classEVENT_1_1LCEvent.html#a9128a3f65b8a94629c0cf5e77c0194ac>
> ()
> const =0
>
> http://lcio.desy.de/v02-04-03/doc/doxygen_api/html/classEVENT_1_1LCEvent.html#a9128a3f65b8a94629c0cf5e77c0194ac
>
> I've created a C library to call from Julia, so I'm happy to convert the
> return type to char**, but I just cannot figure out how to write a ccall
> that doesn't segfault.
> I've seen various examples how to convert a Julia array of strings to a
> char**, but couldn't find anything that converts a char** to Julia types.
>
> Any help is greatly appreciated.
>
> Jan
>
>
