$DISPLAY Environment Variable

The $DISPLAY environment variable tells X clients where to contact your X server. GO-Joe sets this variable to point to an alternate display on your host machine. For example, if your UNIX host is named workstation and the Java device is named java, you might expect the $DISPLAY variable to set java:0 as its value. However, GO-Joe uses the host name for its $DISPLAY variable value, in this case, workstation:1.

GO-Joe makes an additional optimization that can be somewhat confusing. In X parlance, if the $DISPLAY variable is set to unix:#, the JavaStation client attempts to connect using a local transport. For example, instead of using TCP/IP, it connects using a named pipe. This connection is faster than using TCP/IP for clients running on the same host. However, the unix:# value cannot be used if you run clients from different hosts.

Instead, use the following shell script to change the $DISPLAY variable to point to the host name of your machine. This translates $DISPLAY from unix:3, for example, to workstation:3 enabling X clients on other machines to successfully contact GO-Joe on the workstation host. This can be included in the .profile file:

DISPLAY=`/bin/uname -n``/bin/expr $DISPLAY : '[^:]*\(:.*\)'`