PARTIAL SUPPORT FOR 64-BIT TEX LIVE The batchfile tl64.bat provides partial support for 64-bit TeX Live executables. It does this by downloading and adding 64-bit binaries; details under INVOCATION. It also creates a new menu item for a command prompt in which the 64-bit binaries have priority over their 32-bit counterparts. 64-bit executables without 32-bit counterparts are disabled by changing the file extension. BACKGROUND We shall eventually move completely to 64-bit, but there are still TeX users with 32-bit systems, and a 32-bit TeX Live works just fine on a 64-bit Windows. Simultaneous support for both 64-bit and 32-bit Windows would require intricate infrastructure changes, which we hesitate to take on. So in the meantime we offer this makeshift solution, for those people for whom the performance benefits of a 64-bit TeX Live are important. It should work fine as long as both sets of binaries are kept in step, but we cannot guarantee that everything works perfectly. SOME DETAILS The script expects the bin\win32 subdirectory of TeX Live to be on the searchpath. The location of the script itself is not relevant. Some programs may require a 64-bit Ghostscript. If you run into this, you need to install a 64-bit Ghostscript yourself. Outside of this 64-bit command prompt, nothing should change; the TeX Live infrastructure will still be 32-bit. It appears that 32-bit programs and 64-bit programs can invoke each other seamlessly. If this batchfile do not suit your particular case, you can download tl-win64.zip yourself from https://mirror.ctan.org/systems/windows/TLW64/ and integrate it manually. Please also consult 00README.TLW64 from the same CTAN directory. INVOCATION tl64 help - Display a help text and exit. tl64 - Download and install. Old versions are replaced silently. tl64 install - as above. tl64 - Install 64-bit binaries from instead of downloading. tl64 rescan - Recheck which binaries should be deactivated, e.g. when packages have been added or removed. tl64 remove - Remove 64-bit binaries and the 64-bit menu item. WARNING ABOUT FORMAT FILES Occasionally, there might be an update of a TeX engine between releases, which might cause trouble. In that case, you should rerun this script and regenerate formats.