mem@zinn.MV.COM (Mark E. Mallett) (10/26/88)
In article <171@libove.UUCP> root@libove.UUCP (Jay M. Libove) writes: > > While I am using it manually, if a cron job comes up that calls > /usr/lib/uucp/uucico, the LCK.. file in /usr/spool/uucp/ will be ignored > and I will get the modem commands being fired out on the line while I > am connected over it! As yet, this has beena nuisance, but I suppose it > stands to be damaging eventually. Perhaps I am speaking out of turn here, because this is the xenix group and I am speaking of the same problem in the Microport uucico, but this looks like the same problem. When I installed HDB uucp on my Microport Sys V/AT system, I was careful (in the face of having NO documentation, of course) to investigate the format of the new LCK files and change my local comm programs accordingly. Under the HDB convention, each lock file contains the decimal-ASCII number of their owner process - a 10-digit field followed by a newline. I found that even when my comm programs were constructing LCK files with this convention, they were being ignored. A probable reason did occur to me. uucico is likely checking to see if the lock's owner process exists. It is doing this by sending a zero (0) signal (i.e., kill) to that process; a successful return from kill() means that the process does indeed exist. The problem is that an error return from kill() does not necessarily mean that the process does not exist. It can often mean that the process performing the kill() does not have permission to send the signal to the process owning the lock. As proof of this, I tried running my comm programs under ownership of uucp, and the LCK file that they created were indeed honored by uucico, which was also running as uucp. This is not a very good situation. If this is indeed the answer, I suggest that SCO (and Microport) fix uucico to be more intelligent in interpreting the result from the kill() of the LCK owner process. -mm- -- Mark E. Mallett Zinn Computer Co/ PO Box 4188/ Manchester NH/ 03103 Bus. Phone: 603 645 5069 Home: 603 424 8129 uucp: mem@zinn.MV.COM ( ...{decvax|elrond|harvard}!zinn!mem ) BIX: mmallett