Jim,
loading a specific version of a shared library requires two things:
a. Use absolute path to the library in the cffi lib spec b. Make sure the dependencies (see output of otool -L ) (the paths to the dependencies) are at the beginning of the paths set in the environment variable DYLD_LIBRARY_PATH.
Best Frank
-- Frank Gönninger DG1SBG Consequor Consulting AG
Am 20.09.2016 um 16:46 schrieb Jim Newton jimka.issy@gmail.com:
Hi Frank, thanks for the information. If you always use /usr/local/lib then what do you do when you need to run two different independent applications which have different requirements?
On Tue, Sep 20, 2016 at 3:44 PM, Frank Goenninger frgo@me.com wrote: Am 20.09.2016 um 15:32 schrieb Luís Oliveira luismbo@gmail.com:
On Tue, Sep 20, 2016 at 10:53 AM, Jim Newton jimka.issy@gmail.com wrote:
CL-USER> (cffi::list-foreign-libraries) (... #<CFFI:FOREIGN-LIBRARY :LIBCAIRO #P"/usr/local/Cellar/cairo/1.12.16_1/lib/libcairo.dylib" (truename=#P"/usr/local/Cellar/cairo/1.12.16_1/lib/libcairo.2.dylib")>) CL-USER>
However, when I attempt to load libgdk-x11-2.0.0.dylib it complains that it cannot find a particular symbol in /usr/local/lib/libcairo.dylib. Why is it complaining about /usr/local/lib/libcairo.dylib?
Most of those dylibs are symlinks and libgdk may depend on a name which exists in /usr/local/lib but not /usr/local/Cellar, maybe? ldd can tell you what a given dylib depends on.
As Jim is on macOS there is no ldd. The command to use is
otool -L /usr/local/lib//libcairo.dylib
Seeing that Jim uses homebrew to install Cairo it is worth mentioning that brew install … also generates (normally) an entry in /usr/local/lib . That is why I always stick to using /usr/local/lib/libxyz.dylib paths when I want to ensure a particular library to be loaded.
Best, Frank