This is a CMake Environment Variable. Its initial value is taken from the calling process environment.

On UNIX one can use the DESTDIR mechanism in order to relocate the whole installation. DESTDIR means DESTination DIRectory. It is commonly used by packagers to install software in a staging directory.

For example, running

make DESTDIR=/package/stage install

will install the software using the installation prefix, e.g. /usr/local, prepended with the DESTDIR value which gives /package/stage/usr/local. The packaging tool may then construct the package from the content of the /package/stage directory.

See the CMAKE_INSTALL_PREFIX variable to control the installation prefix when configuring a build tree. Or, when using the cmake(1) command-line tool's --install mode, one may specify a different prefix using the --prefix option.


DESTDIR may not be used on Windows because installation prefix usually contains a drive letter like in C:/Program Files which cannot be prepended with some other prefix.