[quote author=Nick Gammon link=topic=124558.msg936296#msg936296 date=1348702675]A tip though, the compiler won't copy the library to the temporary folder it compiles in if the include file is not also in the main sketch (.ino file).[/quote]Why not? It certainly is supposed to!
Okay, so if I point the compiler directly at the file e.g. #include <C:\Users... and specify the entire path, then I get a different set of errors as follows:
RCXIR\RCXIR.cpp.o: In function `RCXIRsetup(unsigned char, unsigned char)':
C:\Users\Family\Dropbox\Matt's Technology\Arduino\Sketch Book\libraries\RCXIR/RCXIR.cpp:18: multiple definition of `FIFO'
RCXIR_Test.cpp.o:(.bss.FIFO+0x0): first defined here
RCXIR_Test.cpp.o: In function `global constructors keyed to FIFO':
RCXIR_Test.cpp:(.text._GLOBAL__I_FIFO+0x4): undefined reference to `FIFOClass::FIFOClass()'
RCXIR\RCXIR.cpp.o: In function `global constructors keyed to FIFO':
RCXIR.cpp:(.text._GLOBAL__I_FIFO+0x4): undefined reference to `FIFOClass::FIFOClass()'