directory name ifndef
key x is not defined
ifndef, if key is not defined
See also &{link:ifdef} and &{link:if}.
ifdef. _DirName_ directory name ${_DirName_}
ifndef. _DirName_ directory name _DirName_ is not defined
ifdef. x value of key x is ${x}
ifndef. x key x is not defined
Long lines are wrapped in this listing.
Use your web browser's "View Page Source" feature to examine the HTML