The need for this is that:
- On OS X if libraries are stored in custom locations (not /usr/lib or /usr/local)
and they do not embed an rpath (which is common to not have) then the developer
needs to set DYLD_LIBRARY_PATH to ensure that osrm tools can find dependent libraries
at runtime (this is normal and common).
- But as of OS X > 10.11 DYLD_LIBRARY_PATH no longer is inherited. While it works in
the main shell when running a command like `osrm-extract` you will find that when
`osrm-extract` is run by cucumber (ruby child process) then DYLD_LIBRARY_PATH
is blocked and the command cannot start.
- So, this introduces the ability to pass in a variable that the cucumber tests will
understand and can manually forward along to ensure that DYLD_LIBRARY_PATH is respected
where it counts.
The intended usage of this is therefore:
# set the environment variable
export OSRM_SHARED_LIBRARY_PATH=${DYLD_LIBRARY_PATH}
# then run cucumber tests
cucumber -p verify
