#### 2.6.4 Environment Variables for Microsoft Windows

These environment variables are specific to the Microsoft Windows implementation.

`MITSCHEME_FONT`

  A string specifying a font name and characteristics, for example ‘`Courier New 16 bold`’. Allowed characteristics are integer, specifying the font size in points, and the following style modifiers: ‘`bold`’, ‘`italic`’, ‘`regular`’, ‘`underline`’ and ‘`strikeout`’. You should specify only fixed-width fonts as variable-width fonts are not drawn correctly.

  Once in Edwin, the font can be changed with the `set-font` and `set-default-font` commands.

`MITSCHEME_GEOMETRY`

  Four integers separated by commas or spaces that specify the placement and size of the MIT/GNU Scheme window as a left,top,width,height quadruple. The units are screen pixels, and ‘`-1`’ means allow the system to choose this parameter. E.g. ‘`-1,-1,500,300`’ places a 500 by 300 pixel window at some system-determined position on the screen. The width and height include the window border and title. The default value is ‘`-1,-1,-1,-1`’.

`MITSCHEME_FOREGROUND`

  A value specifying the window text color. The color is specified as hex blue, green and red values (not RGB): e.g. `0xff0000` for blue.

`MITSCHEME_BACKGROUND`

  A value specifying the window background color. See `MITSCHEME_FOREGROUND`.

`HOMEDRIVE`
`HOMEPATH`

  These variables are used together to indicate the user’s home directory. This is the preferred way to specify the home directory.

`USERNAME`
`USER`

  Specifies the login name of the user running Scheme. This is used for several different purposes. `USERNAME` is preferred; `USER` is used if `USERNAME` is not defined. If neither of these variables is defined, an error is signalled when the username is required.

`USERDIR`

  Specifies a directory that contains the home directories of users. One of the places in which Scheme looks for the user’s home directory, by searching for a subdirectory with the user’s login name.