kevin@msa3b.UUCP (Kevin P. Kleinfelter) (07/21/89)
One final note in my AIX modem battles: I got a callback from IBM yesterday. They said that I should just set "prototol" to "DTR" instead of "DC". This causes the proper minor device number to be set. When I pointed out that this parameter (in devices) is completely undocumented, and that the printed example devices screens do NOT include this parameter, they said "oh." I asked them to find out what this parameter means, AND what the extra bit in the minor device number which it varies means. They said they'd have to call back. When they did, the only explanation they could offer was You set it to DC for direct-attached terminals. You set it to DTR for modem-attached terminals. I just love undocumented features. Also, there seems to be a problem when you call IBM in talking to someone who understands the questions (and also you can end up talking to someone who doesn't understand the ANSWERS!) The doc for AIX PS/2 has several errors (such as an incorrect index, omitted parameters, etc). Also, a "cute" aside: When I installed the system, I ran "devices" and set all the documented parameters. When I ran into "protocol", I did not know what "dtr" and "dc" meant in this context. (I assumed "dc" = "data carrier detect".) However, since it was only one parameter, I figgured that if it did not work one way, I could try the other. Unfortunately I tried the wrong one first. If you use dc first, it creates minor device 96. If you interrupt an open on a 96, which is waiting (forever) on CD, the port is hosed until you either reboot, or run an open on the 96 which succeeds because CD was high before the open. I just tried one value and then the other, and neither worked. Now I can proceed to real work: I'll post my opinions of AIX PS/2 after I learn more. (I'll try to limit further postings to comp.unix.i386.) Thanks to all who offered helpful suggestions. -- Kevin Kleinfelter @ Management Science America, Inc (404) 239-2347 gatech!nanovx!msa3b!kevin