Re: [PATCH] Guard against random bash bug

[Dominique Quatravaux]

Le 14 déc. 2016 à 21:46, Michael Albinus <address@hidden> a écrit :

$val
itself could be '' (two single quotation marks), telling us "the empty
string". With your patch, '' would be taken literally.

Hmm, I did some tests like this (if you'll pardon the pedestrian style),

(setq tramp-remote-process-environment (setenv-internal tramp-remote-process-environment "TEST1" "''" t))

(setq tramp-remote-process-environment (setenv-internal tramp-remote-process-environment "TEST2" "\"" t))

(setq tramp-remote-process-environment (setenv-internal tramp-remote-process-environment "TEST3" "'" t))

(setq tramp-remote-process-environment (setenv-internal tramp-remote-process-environment "TEST4" "$" t))

(setq tramp-remote-process-environment (setenv-internal tramp-remote-process-environment "TEST5" "' )" t))

(setq tramp-remote-process-environment (setenv-internal tramp-remote-process-environment "TEST6" "!true" t))

and it all came out correctly:

kilimandjaro:~$ env|grep TEST

TEST4=$

TEST1=''

TEST6=!true

TEST2="

TEST3='

TEST5=' )

I seem to remember from "man bash" that double quotes protect against word splits (which happen fairly late themselves), and that variable expansions are not recursive. 

(Although your code does work, too so really it's up to you)

Yours truly,

— 

Dominique Quatravaux
Responsable informatique STI EPFL
+41 21 69 35624