[ILUG] UserA <--> UserB Interaction
blf at utvinternet.ie
Mon Feb 4 19:58:01 GMT 2008
| Date: Mon, 04 Feb 2008 08:54:34 +0100
| From: Paolo Marchiori <paolo at marchiori.net>
| Brian Foster wrote:
| > modify ‘sux’ to use sudo(1) rather than su(1), and to
| > [...] (e.g., “sudo -u USER -b boincmgr ...”) — or perhaps
| exec "sudo -u USER sux -c xthis"
NO. even without trying that, that's very very
1. think about the syntax for a second:
exec "sudo -u USER sux -c 'xthis ...'"
(note the added missing '-quotes, need because
<xthis> has some arguments <...>). that will
clearly result in an error, similar to:
bash: exec: xthis ...: not found
2. correcting by elimating the "-quotes (and also
elimating the ‘exec’ since it is not germaine):
sudo -u USER sux -c 'xthis ...'
still won't work. the sudo(1)'ed command won't
have access to the X11 display, which is the
basic problem we're trying to solve here!
the fact the ‘sudo’ed command is sux(1) does not
matter. the ‘sudo’ing looses access to the X11
display. the ‘sux’ is then actually pointless.
and it is also silly, since no user is specified,
hence the ‘sux’ will try to ‘su’ to the superuser
(“root”), which (in this case) is un-necessary.
a test of a corrected command line (also using the
wanted ‘sudo’ ‘-b’ option) shows the predications
to be correct:
$ sudo -u USER -b sux -c 'xthis ...' USER
Password: [type in USER's password]
$ /usr/X11R6/bin/sux: line 143: /home/blf/.Xauthority: Permission denied
cat: /home/blf/.Xauthority: Permission denied
Password: [‘su’ run by backgrounded sux(1) reads /dev/null]
su: incorrect password
“How many surrealists does it take to | Brian Foster
change a lightbulb? Three. One calms | somewhere in south of France
the warthog, and two fill the bathtub | Stop E$$o (ExxonMobile)!
with brightly-coloured machine tools.” | http://www.stopesso.com
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