OS-Specific Library Search Paths

This section is not about building Soar, but running the executables that you've built.


In Linux, the GNU linker provides an -rpath flag that hard codes library search paths into executables. We use this flag for all native executables, such as TestCLI and TestSoarPerformance. These paths are set assuming that the executables and required libraries (specifically libSoar.so) reside in the same directory, which is the default build behavior. Therefore, as long as you don't move the executables or libraries to different relative directories, you should be able to just run the executables without doing anything special. If you are having problems, you should manually set LD_LIBRARY_PATH.

Mac OS X

Dynamic libraries on OS X have the concept of install_name. Basically, shared libraries have a full path hard-coded into them when they are built, and when executables link against the library, they record those paths as the places they'll look for the library at runtime. For more details, see


We set the install_name of libSoar.dylib to be "@executable_path/libSoar.dylib", which means that every executable will look for the Soar library in the same directory as itself. For the executables that are built with Soar, such as TestCLI and TestSoarPerformance, you should be able to just run them without any problems. If you are having problems, you should manually set DYLD_LIBRARY_PATH.

When you build your own SML program and link it against libSoar.dylib, your program will also think that the library is in the same directory as itself, and will not load properly if it isn't. You can fix this either by setting DYLD_LIBRARY_PATH as described above or by changing libSoar.dylib's install_name to an absolute path using the install_name_tool program. In the latter case, every program you build from then on will look for the library using the absolute path, which should not fail unless you move the library or rebuild it.

Please consult the system man page for that command for further information.


Windows searches the executable's directory for needed libraries by default, and since all Soar libraries and executables are in the same directory, there shouldn't be any library not found errors. If you are building your own SML client programs, either put them in the same directory as Soar.dll, or add the directory that contains Soar.dll to your PATH environment variable. For more information about library search order, see


If You have Trouble With The Above

Because the Soar libraries are not installed to standard locations such as /usr/lib on Linux or C:\Windows\System32 on Windows, the operating system may not know where to look for them, depending on what you're trying to run. This is probably the biggest and most frequently encountered problem when getting Soar up and running.

The most straightforward way to solve this problem is to tell the OS where to look. In Linux, this means setting the LD_LIBRARY_PATH environment variable to include the directory libSoar.so is in. Similarly on Mac OSX, you should set DYLD_LIBRARY_PATH. On both operating systems, the command for setting the environment variable should look like:

export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/directory/of/your/Soar/library


export DYLD_LIBRARY_PATH=$DYLD_LIBRARY_PATH:/directory/of/your/Soar/library

Note that you can't put spaces around the =, and you have to use export so that the variable will be inherited by child processes.
In Windows, you should set PATH to include the directory containing Soar.dll.

The rest of this section contains explanations of what's going on under the hood of every operating system so that you'll have some insight should you run into issues.

Java Search Paths

The Java virtual machine has two sets of search paths: the class path and the library path. In general, java classes and jars are searched for in the class path, and native libraries that are loaded by JNI are searched for in the library path. Running Java SML clients requires you to set both correctly.

The SWIG generated SML wrapper classes are contained in sml.jar, so you need to include its path (not the path to the directory containing the jar) in the class path. Those classes in turn load the Java_sml_ClientInterface and Soar native libraries, so the directory containing these libraries must be in the library path.

You can set the class path either by setting the CLASSPATH environment variable (remember to export in Linux and OSX), or passing a command line switch to the java executable:

java -cp /path/to/sml.jar

By default, the JVM will include the LD_LIBRARY_PATH and DYLD_LIBRARY_PATH environment variables in the library path in Linux and OS X, respectively. In Windows the current working directory and the PATH environment variable is included by default. You can manually set the library path by passing a command line switch to the java executable:

java -Djava.library.path=/directory/of/your/Soar/library

Note that while you can also set java.library.path at runtime using Java code, you have to use some hacks to make the virtual machine actually acknowledge the changes. See this page for more information:


Python Search Paths

Like with Java, SWIG also generates a Python wrapper, called Python_sml_ClientInterface.py as well as a native library called_Python_sml_ClientInterface.so (.pyd in Windows) for the Python interface. Unlike Java, Python only has one list of directories where it looks for both files, contained in sys.path. On all operating systems, this list will include the directories in the environment variable PYTHONPATH. You can also set sys.path directly in your python script. For example:

import sys sys.path.append('/directory/of/your/Soar/library')
import Python_sml_ClientInterface as sml