From - Sat Dec 30 21:42:27 2000 Path: reader4.news.rcn.net!feed1.news.rcn.net!feed2.news.rcn.net!rcn!news2.best.com!news-hog.berkeley.edu!ucberkeley!newsfeed.stanford.edu!paloalto-snf1.gtei.net!news.gtei.net!newsgate.tandem.com!mailint03.im.hou.compaq.com!xdelta!hoffman From: hoffman@xdelta.zko.dec.nospam (Hoff Hoffman) Newsgroups: comp.os.vms,comp.sys.dec,vmsnet.alpha,vmsnet.misc,comp.answers,news.answers Subject: OpenVMS Frequently Asked Questions (FAQ), Part 2/5 Followup-To: poster Date: 29 Dec 2000 20:29:04 GMT Organization: Compaq Computer Corporation Lines: 2099 Approved: news-answers-request@mit.edu Distribution: world Expires: 29 Mar 2001 00:00:00 GMT Message-ID: <92is6g$f4j$2@mailint03.im.hou.compaq.com> References: <92irts$f4j$1@mailint03.im.hou.compaq.com> Reply-To: hoffman@xdelta.zko.dec.nospam NNTP-Posting-Host: 16.32.80.251 X-Trace: mailint03.im.hou.compaq.com 978121744 15507 16.32.80.251 (29 Dec 2000 20:29:04 GMT) X-Complaints-To: usenet@mailint03.im.hou.compaq.com NNTP-Posting-Date: 29 Dec 2000 20:29:04 GMT Summary: This posting contains answers to frequently asked questions about the OpenVMS operating system from Compaq Computer Corporation, and the computer systems on which it runs. X-Newsreader: mxrn 6.18-32 Xref: reader4.news.rcn.net comp.os.vms:294264 comp.sys.dec:90011 vmsnet.alpha:10829 vmsnet.misc:6685 comp.answers:44251 news.answers:200647 Archive-name: dec-faq/vms/part2 Posting-Frequency: monthly Last-modified: 29 Dec 2000 Version: VMS-FAQ-2.TXT(5) This is the OpenVMS Frequently Asked Questions Part 2/5. Please see Part 1/5 for administrivia, indexing, archiving, etc. ------------------------------------------------------------ MGMT1. What is an installed image? The term "install" has two distinct meanings in OpenVMS. The first relates to "installing a product", which is done with either the SYS$UPDATE:VMSINSTAL.COM command procedure or the POLYCENTER Software Installation (PCSI) utility (PRODUCT command). The second meaning relates to the use of the INSTALL utility, which is what concerns us here. The INSTALL utility is used to identify to OpenVMS a specific copy of an image, either executable or shareable, which is to be given some set of enhanced properties. For example, when you issue the SET PASSWORD command, the image SYS$SYSTEM:SETP0.EXE is run. That image needs to have elevated privileges to perform its function. The other important attribute is /SHARED. This means that shareable parts of the image (typically read-only code and data) are loaded into memory only once and are shared among all users on a system. Executable images can be installed /SHARED as well as shareable library images. (The term "shareable" has dual meanings here, too. See the OpenVMS Programming Concepts Manual for further details.) It's important to note that there is no such thing as "installing a shareable image with privileges". The INSTALL utility will let you do it, but the privileges you specify will be ignored. To have a callable routine run with enhanced privileges that are not available to its caller, you must construct your routines as "user-written system services" and install the shareable image with the /PROTECT qualifier. See the OpenVMS Programming Concepts Manual for more information on user-written system services. Note also that in many cases the need to grant privileges to an image can be replaced with the use of the "Protected Subsystems" feature that grants a rights identifier to an image. See the OpenVMS Guide to System Security for information on Protected Subsystems. ------------------------------------------------------------ MGMT2. Are there any known viruses for OpenVMS? Viruses are very common on PCs because the PC operating systems such as MS-DOS and MacOS do not implement any sort of scheme to protect the operating system or the file system against hostile action by programs. On these operating systems, any running program can subvert the operating system and take over the hardware, at which point it can do anything it wishes, including hiding copies of itself in other programs or in the file system. This is unlikely on OpenVMS, Unix, and MVS for three reasons. First, the operating system runs in a privileged mode in memory that is protected