The mj-linux-x86_64 binary distribution was compiled under Xubuntu 18.04. It should run on several modern distributions.
The normal Linux binaries are in the Linux directory.
For Debian users: xmj is part of Debian, as a package called mah-jong.
For Fedora: it's in the package mj.
For FreeBSD, it's games/mahjong.
However, the packages are several versions out of date, so don't use them.
The current mj-win32-i686 (gtk2 only) is cross-compiled using MinGW32 under Xubuntu 18.04
The binaries are in the Windows directory.
For the current distribution, and some older -gtk2
distributions, the necessary DLLs are included in the zip
file (which is why it's so large).
For the (very obsolete) -gtk1 distribution, you need (if you have not downloaded them
before) the libraries in the gtkdlls1.zip (1.8MB) file
which you will
also find in the Windows directory. The contents of this
file should be unpacked into the folder of the mj program.
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