On Thu, Jan 17, 2013 at 10:33 AM, Albert-Jan Roskam <fo...@yahoo.com> wrote: > > The goal is to load the C libraries (dll, so, dylib, etc) that my program > needs. > > Anyway, I looked up your two suggestions about library_dirs and > runtime_library_dirs. What is meant by "at link time"?
library_dirs adds search paths for the linker (e.g. ld) for finding shared libraries (.so) and static libraries (.a archives of relocatable object files). Linking to a shared library is handled by the runtime loader/linker (e.g. /lib/ld-linux.so.2). For Linux, ld.so searches the system-defined directories (/lib, /usr/lib, and those set by /etc/ld.so.conf), which are cached in /etc/ld.so.cache (created by ldconfig). This is where distutils runtime_library_dirs comes into play. For ELF it configures an embedded RPATH, which the loader searches before the system directories. You can also convert the RPATH to a RUNPATH, which can be overridden by LD_LIBRARY_PATH. > Does this mean that the ELF header of the library itself is modified readelf -d shows the .dynamic section (including strings from .dynstr), which you can use to verify the RPATH/RUNPATH. chrpath lets you change (but not add) an RPATH, up to its existing length. It also lets you convert an RPATH to a RUNPATH. patchELF can add or extend an RPATH/RUNPATH. http://nixos.org/patchelf.html > The libraries I am using are copyrighted (one can freely use them, but > no reverse engineering, disentangling, etc). I am not sure whether > adding an rpath will be copyright infringement. Logically, I'd say no, > but I doubt whether logic applies in legal stuff. It should be OK for internal administration. You'd have to ask a legal expert about distribution. If you stick with LD_LIBRARY_PATH, etc, keep in mind it has to be set before the process starts, typically in a wrapper script. On Windows, however, you can modify PATH at runtime. _______________________________________________ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
