[R-SIG-Mac] New message from OS (Mountain Lion) with system command

[Dennis Fisher]

Colleagues,

I recently upgraded my OS to Mountain Lion.  Previously, when ran R from a terminal and I issued the command:
	PSOUTPUT	<- system("ps", intern=TRUE)
the output returned without a problem.

Since upgrading to Mountain Lion (R 2.15.1), the same command returns the message:
	dyld: DYLD_ environment variables being ignored because main executable (/bin/ps) is setuid or setgid 
Issuing the "ps" command directly from the terminal or from Rgui does not create the same behavior.

I tracked the problem down to the following.  Running R in a terminal:
	> grep("DYLD", system("set", intern=T), value=T)
	 [1] "DYLD_LIBRARY_PATH=/Library/Frameworks/R.framework/Resources/lib/x86_64" 
Executing the same command from Rgui:
	> grep("DYLD", system("set", intern=T), value=T) 
	character(0) 
And, in a terminal:
	set | grep DYLD 
returns nothing.

It appears that R64, but not Rgui, sets DYLD_LIBRARY_PATH.  Can anyone offer an explanation?  I discovered that:
	Sys.unsetenv("DYLD_LIBRARY_PATH") 
prevents the problem.  Do I incur any hidden risks by executing that command?

Dennis

Dennis Fisher MD
P < (The "P Less Than" Company)
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