SDEHOME

From Wiki.GIS.com

SDEHOME is an environment variable set during the installation of ArcSDE. SDEHOME is where the ArcSDE executables, configuration, and diagnostic files and utilities are stored. It also determines on which ArcSDE service the administrative commands will operate.

[edit] Windows (%SDEHOME%)

• For ArcGIS 9.2 and lower, the default is: C:\arcgis\arcsde\<database exe>
• For ArcGIS 9.3 and higher, the default is: C:\Program Files\arcgis\arcsde\<database exe>

[edit] Unix/Linux ($SDEHOME)

• The SDEHOME location is established by the admin performing the installation