There are some general instructions here:
http://wiki.tcl.tk/12099
Basically, you download tcllib-1.9.tar.gz from the sourceforge.net download page (you can find it from http://tcllib.sourceforge.net/). Put the file in a temporary location on your Cloverleaf system, then execute the following commands:
gzip -cd tcllib-1.9.tar.gz | tar xfv –
cd tcllib-1.9
hcitcl installer.tcl -no-apps -no-examples -pkg-path $HCIROOT/tcl/lib/tcllib1.9 -nroff-path $HCIROOT/tcl/man/mann
After that, you can remove the TAR file and extracted files from your temporary location.
I haven’t tested this very extensively.
Another option, if you don’t want to go through all of the above, is to have your TCL code write your data out to a file and use the “exec” command to call the system “uuencode” command to encode the data. Then, you can read the data back in to your TCL proc. The code to do this probably won’t be as simple as using TCLLIB, but there is nothing extra that you would have to install to get it working.
Also, if you upgrade Cloverleaf in the future, reinstalling this library will have to become part of your upgrade process.