# Installing CMake package config files for MacOS frameworks
**URL:** https://discourse.cmake.org/t/installing-cmake-package-config-files-for-macos-frameworks/849
**Category:** Code
**Created:** [March 24, 2020, 10:07am UTC](https://discourse.cmake.org/t/installing-cmake-package-config-files-for-macos-frameworks/849 "2020-03-24T10:07:32Z")
**Posts on this page:** 6
**Page:** 1
### Author:  [@vre](https://discourse.cmake.org/u/vre)
#### Post date: [March 24, 2020, 10:07am UTC](https://discourse.cmake.org/t/installing-cmake-package-config-files-for-macos-frameworks/849/1 "2020-03-24T10:07:33Z")
I created a versioned MacOS framework with CMake and stumbled over the question where to install the package config files `sample-config.cmake`, `sample-config-version.cmake`, `sample-exports.cmake`, `sample-exports-release.cmake`.
The framework is versioned so the structure is roughly as follows:
```
|-- Headers # link to Versions/Current/Headers
|-- Resources # link to Versions/Current/Resources
+-- Versions
|-- Current # link to B
+-- B
|-- Headers
+-- Resources
|-- CMake
+-- Info.plist
```
I use CMakes `CMakePackageConfigHelpers` macros to generate a package config file from a template `sample-config.cmake.in` with the content
```
@PACKAGE_INIT@
include("${CMAKE_CURRENT_LIST_DIR}/sample-export.cmake")
```
CMake does not mention versioned frameworks and recommends to install the files into the directory `Resources/CMake`.
I did so by calling
```
install(FILES "${CMAKE_CURRENT_BINARY_DIR}/sample-config.cmake"
DESTINATION sample.framework/Resources/CMake
COMPONENT development
)
```
The generated file looks like this:
```
####### Expanded from @PACKAGE_INIT@ by configure_package_config_file() #######
####### Any changes to this file will be overwritten by the next CMake run ####
####### The input file was sample-config.cmake.in ########
get_filename_component(PACKAGE_PREFIX_DIR "${CMAKE_CURRENT_LIST_DIR}/../../../" ABSOLUTE)
macro(set_and_check _var _file)
set(${_var} "${_file}")
if(NOT EXISTS "${_file}")
message(FATAL_ERROR "File or directory ${_file} referenced by variable ${_var} does not exist !")
endif()
endmacro()
macro(check_required_components _NAME)
foreach(comp ${${_NAME}_FIND_COMPONENTS})
if(NOT ${_NAME}_${comp}_FOUND)
if(${_NAME}_FIND_REQUIRED_${comp})
set(${_NAME}_FOUND FALSE)
endif()
endif()
endforeach()
endmacro()
include("${CMAKE_CURRENT_LIST_DIR}/sample-export.cmake")
```
**Error:**
There’s a difference in the generated config file whether I install those files to `Resources/CMake` or to `Versions/B/Resources/CMake` although both point to the same directory.
When installing via the `Resources` link to `Resources/CMake` the call to set `PACKAGE_PREFIX_DIR` is generated as
```
get_filename_component(PACKAGE_PREFIX_DIR "${CMAKE_CURRENT_LIST_DIR}/../../../" ABSOLUTE)
```
but when installing via `Versions/B/Resources/CMake` it is generated as
```
get_filename_component(PACKAGE_PREFIX_DIR "${CMAKE_CURRENT_LIST_DIR}/../../../../../" ABSOLUTE)
```
As a consequence of this the package cannot be found by `find_package(sample CONFIG)` when installing to `Versions/B/Resources/CMake`.
Did anybody was facing this error before?
Thanks for any input on this.
---
### Author:  [@ben.boeckel](https://discourse.cmake.org/u/ben.boeckel)
#### Post date: [March 24, 2020, 4:40pm UTC](https://discourse.cmake.org/t/installing-cmake-package-config-files-for-macos-frameworks/849/2 "2020-03-24T16:40:05Z")
It seems like also searching `Versions/B` for `Resources/CMake` is a reasonable thing to do to me. Thoughts @brad.king?
---
### Author:  [@brad.king](https://discourse.cmake.org/u/brad.king)
#### Post date: [March 24, 2020, 5:42pm UTC](https://discourse.cmake.org/t/installing-cmake-package-config-files-for-macos-frameworks/849/3 "2020-03-24T17:42:26Z")
The [find\_package search procedure](https://cmake.org/cmake/help/v3.17/command/find_package.html#search-procedure) _does_ search `/.framework/Versions/*/Resources/CMake/` inside frameworks. One can see the implementation [here](https://gitlab.kitware.com/cmake/cmake/-/blob/v3.17.0/Source/cmFindPackageCommand.cxx#L2365-2376).
@vre what actually goes wrong?
---
### Author:  [@vre](https://discourse.cmake.org/u/vre)
#### Post date: [March 24, 2020, 6:19pm UTC](https://discourse.cmake.org/t/installing-cmake-package-config-files-for-macos-frameworks/849/4 "2020-03-24T18:19:59Z")
My question is why the `PACKAGE_PREFIX_DIR` is set to different values when installing to `Resources/CMake` and to `Versions/B/Resources/CMake` although both point to the same physical directory? If I have some variables dependent on `PACKAGE_PREFIX_DIR` they will not resolve properly when I use the one or the other path.
---
### Author:  [@brad.king](https://discourse.cmake.org/u/brad.king)
#### Post date: [March 24, 2020, 6:26pm UTC](https://discourse.cmake.org/t/installing-cmake-package-config-files-for-macos-frameworks/849/5 "2020-03-24T18:26:54Z")
The logic generating the code to compute `PACKAGE_PREFIX_DIR` assumes that there are no symbolic links involved. I don’t know if anyone has actually used `CMakePackageConfigHelpers` for a package configuration file inside a framework before.
The presence of symbolic links inside the framework may be problematic. `MyPackage_DIR` can be set by users to be either
- `/MyPackage.framework/Resources/CMake`, or
- `/MyPackage.framework/Versions/Current/Resources/CMake`, or
- `/MyPackage.framework/Versions/B/Resources/CMake`.
In all of those cases we need to be able to recover the ``, but the number of components that needs to be removed is not the same for all cases.
---
### Author:  [@vre](https://discourse.cmake.org/u/vre)
#### Post date: [March 24, 2020, 10:26pm UTC](https://discourse.cmake.org/t/installing-cmake-package-config-files-for-macos-frameworks/849/6 "2020-03-24T22:26:56Z")
Thank you for the enlightening explanations. Good to know that symbolic links are problematic when placing configure files. I can work around that.