GNUInstallDirs

Define GNU standard installation directories

Provides install directory variables as defined by the GNU Coding Standards.

Result Variables

Inclusion of this module defines the following variables:

CMAKE_INSTALL_<dir>

Destination for files of a given type. This value may be passed to the DESTINATION options of install() commands for the corresponding file type.

CMAKE_INSTALL_FULL_<dir>

The absolute path generated from the corresponding CMAKE_INSTALL_<dir> value. If the value is not already an absolute path, an absolute path is constructed typically by prepending the value of the CMAKE_INSTALL_PREFIX variable. However, there are some special cases as documented below.

where <dir> is one of:

BINDIR

user executables (bin)

SBINDIR

system admin executables (sbin)

LIBEXECDIR

program executables (libexec)

SYSCONFDIR

read-only single-machine data (etc)

SHAREDSTATEDIR

modifiable architecture-independent data (com)

LOCALSTATEDIR

modifiable single-machine data (var)

LIBDIR

object code libraries (lib or lib64 or lib/<multiarch-tuple> on Debian)

INCLUDEDIR

C header files (include)

OLDINCLUDEDIR

C header files for non-gcc (/usr/include)

DATAROOTDIR

read-only architecture-independent data root (share)

DATADIR

read-only architecture-independent data (DATAROOTDIR)

INFODIR

info documentation (DATAROOTDIR/info)

LOCALEDIR

locale-dependent data (DATAROOTDIR/locale)

MANDIR

man documentation (DATAROOTDIR/man)

DOCDIR

documentation root (DATAROOTDIR/doc/PROJECT_NAME)

If the includer does not define a value the above-shown default will be used and the value will appear in the cache for editing by the user.

Special Cases

The following values of CMAKE_INSTALL_PREFIX are special:

/

For <dir> other than the SYSCONFDIR and LOCALSTATEDIR, the value of CMAKE_INSTALL_<dir> is prefixed with usr/ if it is not user-specified as an absolute path. For example, the INCLUDEDIR value include becomes usr/include. This is required by the GNU Coding Standards, which state:

When building the complete GNU system, the prefix will be empty and /usr will be a symbolic link to /.

/usr

For <dir> equal to SYSCONFDIR or LOCALSTATEDIR, the CMAKE_INSTALL_FULL_<dir> is computed by prepending just / to the value of CMAKE_INSTALL_<dir> if it is not user-specified as an absolute path. For example, the SYSCONFDIR value etc becomes /etc. This is required by the GNU Coding Standards.

/opt/...

For <dir> equal to SYSCONFDIR or LOCALSTATEDIR, the CMAKE_INSTALL_FULL_<dir> is computed by appending the prefix to the value of CMAKE_INSTALL_<dir> if it is not user-specified as an absolute path. For example, the SYSCONFDIR value etc becomes /etc/opt/.... This is defined by the Filesystem Hierarchy Standard.

Macros

GNUInstallDirs_get_absolute_install_dir

GNUInstallDirs_get_absolute_install_dir(absvar var)

Set the given variable absvar to the absolute path contained within the variable var. This is to allow the computation of an absolute path, accounting for all the special cases documented above. While this macro is used to compute the various CMAKE_INSTALL_FULL_<dir> variables, it is exposed publicly to allow users who create additional path variables to also compute absolute paths where necessary, using the same logic.