The minimum set of Cygwin packages needed to build wc3270 are:
To build wc3270, start a Cygwin shell, cd to the directory where the source code resides, and type:
makewc3270 was developed primarily on 32-bit Windows XP and 64-bit Windows 7, but should be buildable on Windows Server 2003 or Windows 2000 (though Windows 2000 has been known to build defective wc3270 DLLs). It has not been built on 64-bit XP or on Vista.
wc3270 can also be built on Linux with the MinGW cross-compiler. (This is how public releases of wc3270 are built.) On Ubuntu, this compiler is available as the mingw32 package, and the Makefile has been set up to use it. To build wc3270 on Linux with MinGW, use the command:
make CROSS=1
To build an OpenSSL version of wc3270 on Cygwin or Linux, you will need the header files and libraries from the full Win32 OpenSSL distribution described in the SSL Instructions (not the 'lite' version). First, install OpenSSL on your Windows box. Then create a directory called /usr/local/OpenSSL-Win32 under Cygwin or on your Linux system. Then copy the include and lib directories from the OpenSSL distribution on the Windows box (usually located in C:\OpenSSL-Win32) into /usr/local/OpenSSL-Win32 on the Cygwin or Linux system. The Makefile will find them automatically and build an SSL-based wc3270. If for some reason you later want to build a non-SSL wc3270, pass the command-line option NO_SSL=1 to make.
nmake /f Msc\Makefile
This will build wc3270.exe and the DLLs and utilities needed to install and run it.
Note that the resulting version of wc3270 will not include SSL support. To build an OpenSSL version of wc3270 with MSC, you will need the header files and libraries from the full Win32 OpenSSL distribution described in the SSL Instructions (not the 'lite' version). First, install OpenSSL on your Windows box. Then you must modify Msc\Makefile; instructions for doing that are included in the file itself.
The source tarball also includes an .iss file for use with Inno Setup. This is used to construct the install executable. See the Inno Setup webpage for details.