I installed the PROJ.4, GDAL, or one of the support libraries on my system, it is recognized by MapServer’s “configure” as a system lib but at runtime I get an error: “libproj.so.0: No such file or directory”.

You are probably running a RedHat Linux system if this happened to you. This happens because the libraries install themselves under /usr/local/lib but this directory is not part of the runtime library path by default on your system.

(I’m still surprised that “configure” picked proj.4 as a system lib since it’s not in the system’s lib path...probably something magic in autoconf that we’ll have to look into)

There are a couple of possible solutions:

1. Add a “setenv LD_LIBRARY_PATH” to your httpd.conf to contain that directory

2. Edit /etc/ld.so.conf to add /usr/local/lib, and then run “/sbin/ldconfig”. This will permanently add /usr/local/lib to your system’s runtime lib path.

3. Configure MapServer with the following options:

   --with-proj=/usr/local --enable-runpath

   and the /usr/local/lib directory will be hardcoded in the exe and .so files

I (Daniel Morissette) personally prefer option #2 because it is permanent and applies to everything running on your system.