Mkmf isn't finding my shared object to link with

ruby-talk
1

I have an extension I wrote which is actually just a wrapper for a C api.
The directory structure looks like this.
.

-- Makefile
-- extconf.rb
-- extconf.rb~
-- libmdc.so
-- mdc.h
-- metadata-backup.c~
-- metadata.c
-- metadata.c~
-- metadata.o
-- metadata.so

`-- mkmf.log

When I generate the makefile, it doesn't find libmdc.so. How can I fix
this?

require 'mkmf'

have_header("mdc.h")
have_library('libmdc.so','MDOpenConnection')

dir_config('metadata')
create_makefile('metadata')

When I run it, I get

checking for mdc.h... yes
checking for MDOpenConnection() in -llibmdc.so... no
creating Makefile

2

I'm not sure, but I think you shouldn't put the lib prefix in the call to
have_library:

have_library('mdc', 'MDOpenConnection')

I hope this helps

Stefano

···

On Sunday 06 July 2008, Tristin Davis wrote:

I have an extension I wrote which is actually just a wrapper for a C api.
The directory structure looks like this.
.

>-- Makefile
>-- extconf.rb
>-- extconf.rb~
>-- libmdc.so
>-- mdc.h
>-- metadata-backup.c~
>-- metadata.c
>-- metadata.c~
>-- metadata.o
>-- metadata.so

`-- mkmf.log

When I generate the makefile, it doesn't find libmdc.so. How can I fix
this?

require 'mkmf'

have_header("mdc.h")
have_library('libmdc.so','MDOpenConnection')

dir_config('metadata')
create_makefile('metadata')

When I run it, I get

checking for mdc.h... yes
checking for MDOpenConnection() in -llibmdc.so... no
creating Makefile

3

Thanks Stefano, that worked. Now I get this though.

LoadError: libmdc.so: cannot open shared object file: No such file or
directory - ./metadata.so
    from ./metadata.so
    from (irb):1

I tried setting LD_LIBRARY_PATH to include the directory, but that didn't
work.

···

On Sun, Jul 6, 2008 at 12:12 PM, Stefano Crocco <stefano.crocco@alice.it> wrote:

On Sunday 06 July 2008, Tristin Davis wrote:
> I have an extension I wrote which is actually just a wrapper for a C api.
> The directory structure looks like this.
> .
>
> >-- Makefile
> >-- extconf.rb
> >-- extconf.rb~
> >-- libmdc.so
> >-- mdc.h
> >-- metadata-backup.c~
> >-- metadata.c
> >-- metadata.c~
> >-- metadata.o
> >-- metadata.so
>
> `-- mkmf.log
>
> When I generate the makefile, it doesn't find libmdc.so. How can I fix
> this?
>
> require 'mkmf'
>
> have_header("mdc.h")
> have_library('libmdc.so','MDOpenConnection')
>
> dir_config('metadata')
> create_makefile('metadata')
>
> When I run it, I get
>
> checking for mdc.h... yes
> checking for MDOpenConnection() in -llibmdc.so... no
> creating Makefile

I'm not sure, but I think you shouldn't put the lib prefix in the call to
have_library:

have_library('mdc', 'MDOpenConnection')

I hope this helps

Stefano