Setting Environment Variables

By running Cygwin, the setting of environment variables and similar becomes very familiar to a Linux user. In particular, running Xic from a Cygwin bash-shell window emulates pretty well the Linux experience. This is a recommended approach for those familiar with Unix/Linux.

Otherwise, environment variables can be set manually in a Command Prompt window from which the programs are run. The bat files can be modified and ``set'' lines added, as an option to avoid manual setting of variables that should always be in force. Another option is to set the system default environment variables. Be aware that all other programs will see the variables. Setting the system environment variables is probably something to avoid if possible. If you insist, here is the procedure for Windows 8.1. Other supported Windows releases are probably not horribly different.

1. Go to the infamous Start page, click on the circle with down arrow icon near the bottom-left corner. This shifts to the Apps page.

2. Find the Control Panel, it is listed on the Apps page under Windwos System You can use the search tool if necessary. Eventually, you'll find the icon, then click it to bring up the Control Panel.

3. Click System and Security. The display will change to a new set of choices.

4. Click System.

5. Click Advanced system settings along the left. This brings up a System Properties window.

6. Click the Environment Variables button near the bottom of the Advanced page (this page should be shown initially).

There are a couple of things one may want to do here, as examples.

1. Add the XicTools bin directory to the system search path.
   
   Scroll the lower System variables window to find the Path entry. Click on this to select it. Click the Edit... button below, which brings up a text entry window. In the Variable value window, scroll all the way to the right, and add, for example (use the actual paths if different on your system)

   ;c: \ usr \ local \ xictools \ bin

   Check the spelling, and make sure there is no white space, and that the character before the `c' is a semicolon, and the character that follows the `c' is a colon. Then click the OK button.

2. Add a HOME variable to define a ``home directory''.
   
   Press the New... button below the UPPER listing window (not the one you just used). This brings up a text entry as we saw before. Enter HOME for Variable name, For Variable value, enter a path to some directory which you want to be your ``working'' directory, where Xic and WRspice will look for startup files, etc. Enter the full path to this directory. Check spelling, Click OK.

Finally, click the OK button at the bottom of the window, we're done.

When a program is started from an icon, an icon property specifies the directory where the program logically starts from. This is the apparent current directory seen by the user when running the program. By default, this is usually sonething like ``C: \ '', which is not a good choice. The user should have a directory dedicated for this, and the following procedure can be used to cause the programs started from an icon to start in this directory.

1. Go to the Start page, click on the circle with down arrow icon near the bottom-left corner. This shifts to the Apps page.

2. Find the XicTools program group. There should be entries for the programs that you have installed.

3. For each program:
   
   1. Click on the program icon with the RIGHT mouse button. An icon banner along the bottom of the screen will appear.

   2. Click on Open File Location. This brings up a listing showing the XicTools programs.

   3. Above the list, find the Properties icon and click it. This brings up a multi-page Properties pop-up.

   4. In the Shortcut page, change the entry in the Start in entry area to a full directory path to the directory where the program should start. This might be the same directory that you used for the HOME environment variable.

   5. Then click the Apply button, and click OK if there is a confirmation pop-up.

This applies to the icon in the Apps page. Other icons can be set similarly.