Installation with Cygwin using GNU compilers

Cygwin is a Linux-like environment for Windows; if you don't know what it is you might want to have a look at the Cygwin homepage, www.cygwin.com.

It is possible to build the IPOPT AMPL solver executable in Cygwin for general use in Windows. You can also hook up IPOPT to your own program if you compile it in the Cygwin environment¹⁰.

If you want to compile IPOPT under Cygwin, you first have to install Cygwin on your Windows system. This is pretty straight forward; you simply download the ``setup'' program from www.cygwin.com and start it.

Then you do the following steps (assuming here that you don't have any complications with firewall settings etc - in that case you might have to choose some connection settings differently):

1. Click next
2. Select ``install from the internet'' (default) and click next
3. Select a directory where Cygwin is to be installed (you can leave the default) and choose all other things to your liking, then click next
4. Select a temp dir for Cygwin setup to store some files (if you put it on your desktop you will later remember to delete it)
5. Select ``direct connection'' (default) and click next
6. Select some mirror site that seems close by to you and click next
7. OK, now comes the complicated part:
   You need to select the packages that you want to have installed. By default, there are already selections, but the compilers are usually not pre-chosen. You need to make sure that you select the GNU compilers (for Fortran, C, and C++ -- together with the MinGW options), the GNU Make, and Subversion. For this, click on the "Devel" branch (which opens a subtree) and select:
   • gcc
   • gcc-core
   • gcc-g77
   • gcc-g++
   • gcc-mingw
   • gcc-mingw-core
   • gcc-mingw-g77
   • gcc-mingw-g++
   • make
   • subversion

   Then, in the ``Web'' branch, please select ``wget'' (which will make the installation of third party dependencies for IPOPT easier)

   This will automatically also select some other packages.

8. Then you click on next, and Cygwin will be installed (follow the rest of the instructions and choose everything else to your liking). At a later point you can easily add/remove packages with the setup program.

9. Now that you have Cygwin, you can open a Cygwin window, which is like a UNIX shell window.

10. Now you just follow the instructions in the beginning of Sections 2: You download the IPOPT code into your Cygwin home directory (from the Windows explorer that is usually something like C: $\backslash$ Cygwin $\backslash$ home $\backslash$ your_user_name). After that you obtain the third party code (like on Linux/UNIX), type

    ./configure

    and

    make install

    in the correct directories, and hopefully that will work. The IPOPT AMPL solver executable will be in the subdirectory bin (called ``ipopt.exe''). If you want to set the installation, type

    make test

    NOTE: By default, the compiled binaries (library and executables) will be ``Cygwin-native'', i.e., in order to run executables using this, the Cygwin1.dll has to be present (e.g., in a Cygwin window). If you want to compile things in a way that allow your executables to run outside of Cygwin, e.g., in a regular DOS prompt, you need to specify the option `` -enable-doscompile'' when you run configure.