The files here are documented in the paper
"Interfaces to PATH 3.0: Design, Implementation and Usage"
by Michael C. Ferris and Todd S. Munson.

The version that is downloadable from here (i.e. the file pathlib.zip
in this directory) is free, but is limited to problems with less than 
300 variables and 10,000 nonzeros.

The file LICENSE details how to set up a temporary license that removes 
this restriction for a certain length of time.

ampl:

The interfaces for this, and the source for the ampl installation
can be found in the path*.zip archive (these are now indexed by version number and 
by machine architecture i.e. _5.0.05  and _Win64).  This archive contains 
further information on how to proceed.

gams:
Download the complete student version of GAMS from:
   http://www.gams.com/download/
This includes a version of PATH.

gamspy:
GAMSPy comes with a free demo license which lets you generate and solve small models. GAMSPy is free for academics. Please check GAMS Academic Program for details (https://www.gams.com/academics/).  Note that this includes access to the PATH solver for free for academics.

julia:
The library files needed for the PATH.JL interface are found in the julia directory.
See the file "README" in that directory for information.
Currently only provided on OSX, Linux and Windows platforms.
The directory also contains a file "LICENSE" that details how
to set up a temporary license file for the system.

matlab:
Files for setting this up without compilation are found in the matlab directory.
See the file "README" in that directory for information.
Currently only provided on Solaris, Linux and Windows platforms.
The directory also contains a file "LICENSE" that details how
to set up a temporary license file for the system.

Source for the matlab link, complete with makefiles, etc can be found
in the pathlib.zip archive.

standalone_c:
standalone_f:
Versions of the path library can be used and compiled for standalone versions, again in conjunction with the file "LICENSE".

If you have difficulties, please contact 
Michael Ferris by email at ferris@cs.wisc.edu