How do I append to the include path using .rootrc or rootlogon.C?

[Wile_E_Coyote]

You can put there whatever you want.

rootlogon.C documentation

In any ROOT version (also in ROOT 5), either an “unnamed” macro (I somehow remember that the “{” needed to be the very first line in an “unnamed” macro): { // ... } or a “named” macro: void rootlogon() { // ... }