How about 

SmalltalkImage checkChangesFileAvailability: false.

Hi,

in SmalltalkImage>>checkAndOpenSourcesAndChanges, there is some code
that looks like this:

  [...]
  changes isReadOnly
               ifTrue: [ self inform: 'Pharo cannot write to the
changes file ...' ].
  [...]

This code raises a warning if the changes file can't be written to. In
the PharoLauncher case, the image and changes file won't be writable
and it is ok (they will be in a place like /usr/lib). I certainly
don't want my users to see this warning.

What can I do please?

--
Damien Cassou
http://damiencassou.seasidehosting.st

"Success is the ability to go from one failure to another without
losing enthusiasm."
Winston Churchill