I was trying to use the Activity Monitor to do a Sample of an application. When clicking the Sample button, Activity Monitor would generate an error: fopen: Operation not supported Unable to open/create sample file /dev/stdout And sure enough, /dev/stdout was missing. Along with /dev/stdin, /dev/ stderr and the directory /dev/fd! Restarting brought them back, but soon after they were gone again! I have no idea what could be removing those files. This is on Tiger, and on 3 different machines. Anyone have any idea what could cause those files to be deleted? Thanks, John