From: CSBVAX::MRGATE!LEICHTER@Venus.YCC.Yale.Edu@SMTP 17-MAY-1988 09:09 To: ARISIA::EVERHART Subj: re: Where do I look for SYSGEN param on MODEM hangups ? Received: from Venus.YCC.Yale.Edu by KL.SRI.COM with TCP; Sun 15 May 88 12:07:37-PDT Date: Sun, 15 May 88 14:36 EST From: "Jerry Leichter (LEICHTER-JERRY@CS.YALE.EDU)" Subject: re: Where do I look for SYSGEN param on MODEM hangups ? To: ANK@CUNYVMS1.BITNET, INFO-VAX@KL.SRI.COM X-VMS-To: IN%"ANK@CUNYVMS1.BITNET",INFOVAX Of late we have been having problems with some of our MODEM lines. People get HUNG or get a connect and no response, or USER authorization failure. our modems as defined as $ SET TERM TTC1:/AUTOBAUD/DISCONNECT/MODEM/HANGUP/PERM/DIALUP a show term ttcX indicates that some are set as /nohangup even though all are will /HANGUP Eh? What does this line mean? I read in I/O users manual about setting it to HANGUP for all but I am not sure how.? And this one? I listed the SYSGEN params list to find which one's if any were set by default to /nohangup The default terminal parameters are controlled by the TTY_DEFCHAR and TTY_DEFCHAR2 parameters. These are a bit painful to work with since they are bit-encoded, corresponding to the terminal parameters defined in the I/O User's Guide. To manipulate them, you need to figure out which bit in which terminal parameter word is of interest, then set it appropriately. This is really only necessary for a couple of parameters (like DISCONNECT) and mainly for LAT lines, not real terminal lines. The easier way to set the parameters for real terminal lines is as you appear to have done it: With SET TERM/PERM commands issued during system startup. I guess my question is: How can we assure that all modem ports behave exactly as we set them out to be in our above definitions. There are two sets of parameters associated with a terminal line: Active and permanent. Essentially, the permanent ones are copied into the active ones when someone logs in on the line. (This isn't really how it works; in fact, as I recall they really get copied when the last channel to the terminal is deassigned. But it's probably OK to think of it as happening on login for now.) The permanent parameters are then not looked at again until the next login - it is the active ones that control what happens on the terminal line, and it is the active ones that a normal SET TERM changes. They are also what a SHOW TERM will display. No matter what the permanent settings say, if a SET TERM/NOHANGUP is issued, either as a DCL command or by a program doing the equivalent SETMODE QIO, the terminal's active parameters will now say /NOHANGUP, and the line will not be hung up on logout. But...there's an additional factor at play. Because the /HANGUP - /NOHANGUP distinction has security implications, VMS provides a way for the system manager to keep users from screwing around with the setting. Normally, privilege (LOG_IO or PHYS_IO) is required to change the /HANGUP setting. It is possible to allow non-privileged users to change the setting for a particular line by setting the TT2$M_MODHANGUP characteristic for that line. There is no SET TERM qualifier for for this characteristic - it has to be set by a program, or in the TTY_DEFCHAR2 parameter. The bit you want is bit 3 (value 8). (I found that by looking in SYS$LIBRARY:TT2DEF.H, by the way.) If this bit is on, users will be able (by default) to modify the hangup setting. The default setting for this bit, i.e., in the value of TTY_DEFCHAR2 in VMS "out of the box" - is OFF: Users CANNOT modify the hangup setting. Check with SYSGEN to determine if the value on your system has been changed. (CAUTION: The value displayed by SYSGEN is always in decimal, and the values accept by a SYSGEN SET command are normally in decimal, though you can use a %X prefix to enter hex if you want. Dealing with bits in decimal is painful and tricky. Many systems have ended up in strange states when someone screwed up and mixed bases in setting the TTY parameters, flipping some random assortment of bits. Be careful!) Our users are getting paranoid with the semester coming to an end. Having said all that about /HANGUP: It's not clear to me what problems you are actually seeing, or what they have to do with /HANGUP. You've given a vague description, and also provided a guess as to what you think is the cause of the problem you've vaguely described. That makes it very hard for anyone to give you much help. Next time, you would do better to DESCRIBE THE SYMPTOMS YOU ACTUALLY SEE, not what you think is behind them. You may be wrong, in which case you will at best get advice that can only lead you further down an incorrect path. -- Jerry