Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!uunet!snorkelwacker!apple!hercules!cslb.csl.sri.com!kph From: kph@dustbin.cisco.com (Kevin Paul Herbert) Newsgroups: comp.os.rsts Subject: Re: RSTS/E Protection codes. Message-ID: Date: 29 Mar 90 06:02:37 GMT References: <1727@expya.cs.exeter.ac.uk> Sender: usenet@csl.sri.com Followup-To: comp.os.rsts Organization: cisco Systems, Inc. Lines: 38 In-reply-to: cca@cs.exeter.ac.uk's message of 28 Mar 90 19:11:16 GMT Adam Glass (adam@mit-amt.MEDIA.MIT.EDU) did a good job of answering most of the questions. Here are some additional details. >Also if the codes do not permit execute Read OR write to a user - does that >cause the filename to be hidden as well?? It depends on the version of RSTS that you run. Around V7.0, a feature patch wsa released by DEC which caused the directory functions to not report files that a user could not read. Later on, the default changed, and a feature patch came out to change back to the old behavior. Later, the feature patch was dropped entirely. >i.e log in as a 1,* user and see all names login as another user and see only >some filenames. The basic rule is that you can't see what you can't access. For pre-V9.0 systems, this means that [1,*] can see everything, and other accounts are limited based on protection code. For V9.0, people with world read privilege can see all files regardless of protection, people with group read privilege can see all group files, and otherwise it uses protection code. Here are the definitions of bits 6 and 7: bit 6 - Executable file. Change the meaning of all "read" access bits to mean "execute" and "write" to be "read/write". This means that a <104> file is world-execute, but read/write only by owner. That's different than <40>, which is world-read, but read/write only by owner. bit 7 - Privileged file. If this bit is on, the file will get erased by the system when it is deleted, so disk scroungers won't find the data. Further, if bit 6 is on, when run, the program will get termporary privileges. I don't have RSTS manuals anymore, and I don't remember off-hand what SYS(CHR$(4%)) does. It is one of the terminal control functions, but I forget which one. As for the priority change, it is privileged so you wouldn't be able to make use of it anyway. Kevin