[CMake] Only install file if it does not exist?

[Bob Tanner]

I must be missing something simple?

During "make install" I only want to install a set of files if the do 
not exist in destination.

MACRO (COPY_IF_DOES_NOT_EXIST SOURCE DESTINATION)
	ADD_CUSTOM_COMMAND (
		TARGET COPY
		IF (NOT EXISTS ${DESTINATION})
			COMMAND ${CMAKE_COMMAND} -E copy ${SOURCE} ${DESTINATION}
		ENDIF (NOT EXISTS ${DESTINATION})
	)
	
	ADD_CUSTOM_TARGET (
		COPY ALL
		COMMENT "Copy file: ${SOURCE} ${DESTINATION}"
	)
	
ENDMACRO (COPY_IF_DOES_NOT_EXIST SOURCE DESTINATION)

Works the first time, but if I delete the destination file a make 
install won't install it again.

Any help?

-- 
Bob Tanner <tanner at real-time.com>                  | Phone : (952 943-8700
http://www.real-time.com, Linux, OSX, VMware | Fax   : (952)943-8500
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