bug#4309: EMACSDOC

[Gareth Rees]

... in particular, when running in a shell in Emacs.app, the  
environment has

EMACSDOC=/Applications/Emacs.app/Contents/Resources/etc

but no such variable is present when running in a shell in Terminal.app

I suggest that the Emacs build process should be robust to the  
presence of $EMACSDOC and other Emac-specific environment variables,  
otherwise it will be impossible to build one version of Emacs from  
within a shell buffer in a different version of Emacs.

--
Gareth Rees