Using cmd line when multiple quartus versions installed

You cannot do this within Quartus, but you should be able to write a script to achieve what you want. For example, you can have the script change your search path so that when you type quartus_sh, it either finds it from the 9.1 or the 10.0 directories (for example).

If you want to switch automatically based on the project, you will need your script to first get the LAST_QUARTUS_VERSIOON from the QSF, and use that to decide which EXE to call. It should be easy to do using grep/awk or using some higher level scripting language like Perl, Python (or Tcl).

Hope this helps.

DK