╗This file appears to hold pointers into device files, memory maps, etc. ╗which lsof reads the next time around. It could be very dangerous since ╗lsof normally runs as root. Please tell me I'm wrong and it's not a hazard. >From the lsof man page: The device cache file is stored by default in /tmp with read and write permission for owner, group, and user, so any lsof call can access or rebuild it. (You can change the device cache file path with the optional path suffix of the b, r, and u functions.) Lsof can detect that the file has been accidentally or maliciously modi- fied by several sanity checks, including a sixteen bit Cyclic Redundancy Check (CRC) sum of the file's contents. When lsof senses something wrong with the file, it will attempt to remove the current one and create a new copy. The only risk I see is that someone could edit out certain devices. The "-D i" option tells lsof to ignore the cache completely. -Dave