void PEAR_Config::setInstallRoot (
This is used to implement the --installroot option for installation. In earlier PEAR versions, this was implemented in PEAR_Installer::install(), but this makes it more difficult to track with the introduction of channels, and to satisfy better encapsulation, it has been moved to PEAR_Config.
Pass in a full path. On retrieving any directory configuration variable, the
value will be prepended with the installroot specified in this method. For example,
setInstallRoot() is used with
the value returned from get() would be
/hoopla/boo/usr/lib/php. Use an empty string
to reset an installroot.
installation directory to prepend to all _dir variables, or FALSE to disable
throws no exceptions thrown
This function can not be called statically.