// all leading UTF-8-encoded code points c that satisfy f(c).
func TrimLeftFunc(s []byte, f func(r rune) bool) []byte {
	i := indexFunc(s, f, false)
	if i == -1 {
		return nil
	}
	return s[i:]
}

// TrimRightFunc returns a subslice of s by slicing off all trailing
// UTF-8-encoded code points c that satisfy f(c).
func TrimRightFunc(s []byte, f func(r rune) bool) []byte {

	char* _cgo_topofstack(void) { return (char*)0; }
	void _cgo_allocate(void *a, int c) { }
	void _cgo_panic(void *a, int c) { }
	void _cgo_reginit(void) { }

The extra functions here are stubs to satisfy the references in the C
code generated for gcc. The build process links this stub, along with
_cgo_export.c and *.cgo2.c, into a dynamic executable and then lets
cgo examine the executable. Cgo records the list of shared library