-au Filetype c,cpp,objc map <buffer> <F11> :vsplit<CR>:FSRight<CR>
-au Filetype c,cpp,objc map <buffer> <S-F11> :FSHere<CR>
+" Performs a vertial split and a FSHere. For a header file the split is
+" performed to the left, for an implementation file to the right.
+function FSvsplit()
+ " We split to the right on header files
+ if match(expand('%:e'), 'h.*') >= 0
+ execute ':leftabove vsplit'
+ else
+ execute ':rightbelow vsplit'
+ endif
+
+ execute ':FSHere'
+endfunction
+
+au Filetype c,cpp,objc map <buffer> <F12> :call FSvsplit()<CR>
+" Terminal-based vi report S-F12 as F24
+au Filetype c,cpp,objc map <buffer> <S-F12> :FSHere<CR>
+au Filetype c,cpp,objc map <buffer> <F24> :FSHere<CR>