If you are lucky, the system catches the backward link almost immediately, reports it to you, and you take appropriate action. If you are unlucky, the problem goes unresolved until things get really messed up.
How you fix it depends on how it happened. If two processes think they own that block of memory, then there is a good likelihood that one of them links into apparent garbage. You get to figure out how to restore what should have been there. There are many really bad variations, like block 2 of 1000 being used by another process, as though it were free space. Now you've lost blocks 3-1000, since you no longer have a good forward link to the rest of it from block 2, which someone else is using to link into, say 100 blocks of their space. The first user's first block now links to a block that links to 100 other blocks that don't belong to the first user. This is just one of several possible scenarios. What you really want is to avoid it in the first place. If you look at the description below, you will see that the user has two Universe instances. If they both use the same file, then they both think they control the file space, and problems such as I describe above can happen. Someone else on the thread gave several alternate ways to do the task and avoid this problem. In all likelihood, once you get a Blink error, you have lost data. Hopefully you have a way to restore or recreate it. -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of doug chanco Sent: Monday, May 12, 2008 1:58 PM To: [email protected] Subject: [U2] "blink questions" Thanks for the info BUT what kind of error will one see (i.e. does the system crash or display a blink specific error message?) and how would one fix a "blink" error? thanks! dougc Robert Houben wrote: > Blink is short for "Backward link". Two blocks of random memory that > represent a logically contiguous object that is <= two blocks large will have > header data that point to each other. The first will have a forward link to > the second and a zero in the backward link to indicate it's the first in the > chain. The second will have a forward link of zero (no more blocks) and a > backward link to the first. If the second block does not point back (is zero > or references a different block), this implies that something has gone > really, really wrong with the memory management of the system. > > -----Original Message----- > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of doug chanco > Sent: Monday, May 12, 2008 12:00 PM > To: [email protected] > Subject: Re: [U2] Blink Error - Dictionary Related > > For those of us new to universe (or have never heard of it) what exactly > is a "blink error" > > thanks > > dougc > > Martel, Henry wrote: > >> I have a situation were I have a Prod box and a Dev Box both with Universe >> installed. >> >> On the Prod box we have a samba share that is pointing to the Dev box and we >> have voc entries pointing to Dev files. >> >> But when I execute a command such as: Copy from <file> to Test.<file> >> >> The records will copy over to the Dev box, but it always results in a Blink >> error. >> >> Has anyone experienced this or know how to fix it? >> >> Henry M. >> Database Administrator >> >> -----Original Message----- >> From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Bessel, Karen >> Sent: Friday, May 09, 2008 3:57 PM >> To: [email protected] >> Subject: [U2] Blink Error - Dictionary Related >> >> A client is experiencing a blink error when using a certain I-descriptor in >> a SORT, but not in a LIST or SELECT. >> >> >> >> I can't copy the code into the post because of copyright purposes, but this >> is the dictionary item: >> >> >> >> 0001: I >> >> 0002: IF CASE.PERSON.ID # "" THEN >> SUBR("CJ.READ.PERSON",CASE.PERSON.ID,1,"") E >> >> LSE "" >> >> 0003: S;*;"*** No Defendant ***" >> >> 0004: Defendant >> >> 0005: 30L >> >> 0006: S >> >> >> >> The dictionary item referenced by the I-descriptor: >> >> >> >> 0001: A >> >> 0002: 1 >> >> 0003: CASE.PERSON.ID >> >> 0004: >> >> 0005: M >> >> 0006: >> >> 0007: >> >> 0008: >> >> 0009: R >> >> 0010: 8 >> >> 0011: >> >> 0012: COMMON >> >> >> >> Attribute 1 should be single-valued but there are 27 records in this file >> that have multiple values in this field. On our in-house system, we also >> have a handful of records that have multiple values in this field, and I >> can't recreate the problem here. >> > > >> >> There are commons involved in the subroutine referenced by the I-descriptor. >> >> >> >> This issue just came to me and the people who worked on it before did all of >> the data related things I would have done: searched for control characters, >> fix tool, deleted the file then recreated it, etc. >> >> >> >> I don't know if I've provided enough information to explain the >> problem....but has anyone seen this? If you've experienced an >> application-related blink error, I'd be interested in hearing from you. >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> Karen Bessel >> Software Developer >> >> Tyler Technologies, Inc. >> 6500 International Parkway, Suite 2000 >> Plano, TX 75093 >> Phone: 972.713.3770 ext:6227 >> Fax: 972.713.3777 >> Email: [EMAIL PROTECTED] >> Web: http://www.tylertech.com >> ------- >> u2-users mailing list >> [email protected] >> To unsubscribe please visit http://listserver.u2ug.org/ >> ------- >> u2-users mailing list >> [email protected] >> To unsubscribe please visit http://listserver.u2ug.org/ >> > ------- > u2-users mailing list > [email protected] > To unsubscribe please visit http://listserver.u2ug.org/ > ------- > u2-users mailing list > [email protected] > To unsubscribe please visit http://listserver.u2ug.org/ ------- u2-users mailing list [email protected] To unsubscribe please visit http://listserver.u2ug.org/ ------- u2-users mailing list [email protected] To unsubscribe please visit http://listserver.u2ug.org/
