Hi Charles, Thanks for the information. I had not heard of "sudden termination" but after reading your message, I googled it. Apparently it was also around in Snow Leopard, though I certainly never noticed a running app's icon disappearing from the dock until very recently (and I upgraded to Lion recently).
I wonder what the advantage is to having a running app's icon disappear from the dock? By the way, I looked in the Activity Monitor, but I was not sure how to tell which applications were subject to sudden termination. Is there a special flag or something? The work-around of never deleting PDFs does not sound very appealing (I assume you were joking). Perhaps I should assign Adobe Acrobat as the default PDF viewer to avoid this problem with Preview. Thanks again for the help, Gregg On Jul 7, 2012, at 4:52 PM, Charles Dyer wrote: > If you are running Lion or later, it's because Apple thinks that they are > smarter than you are. There is a new for Lion feature named 'Sudden > Termination', and most Apple apps (including Preview) are rigged for it. > Basically, if you have an app which can be Suddenly Terminated (and you can > tell which ones by firing up Activity Monitor and having a look) then, if > that app has been running for a while (and no, I don't know how long 'a > while' is, I haven't experimented) without significant activity (and no, I > don't know what Apple considers 'significant activity') then the system will > terminate it without asking you. Unfortunately sometimes it terminates the > app without notifying all concerned; this means that the icon vanishes from > the Dock, or if it's permanently there, the 'app is in use' light will go > away. However, some things, such as the Trash, don't get the message. > > Work-around: don't put things into the Trash which are in use from an app > which can be Suddenly Terminated. Other work-around: don't use apps which can > be Suddenly Terminated. > > On 07 Jul 2012, at 16:35 , "Dinse, Gregg (NIH/NIEHS) [V]" > <[email protected]> wrote: > >> Hi, >> >> A week or so ago, I wrote to ask why I could not empty the trash. Usually >> the culprit is a PDF and usually I can quit the Preview app and then the >> trash will empty. This did not appear to be the case recently, though at >> least part of the problem turns out to be that the Preview app was still >> running but its icon was not in the Dock, so I did not realize it was still >> running (and thus I did not quit it). >> >> So the new question of the day is: Why does the Preview app disappear from >> my Dock when it is still running? >> >> I have not investigated much, but if I double-click on a PDF while Preview >> is not running, then Preview starts up and its icon shows up in the Dock, >> but at some point (I don't know when or why), the icon disappears from the >> Dock. >> >> By the way, I discovered that Preview was still running by using the What's >> Keeping Me app that someone suggested. Thanks for that suggestion! >> >> And thanks in advance for any information about my latest question. >> >> Gregg _______________________________________________ MacOSX-talk mailing list [email protected] http://www.omnigroup.com/mailman/listinfo/macosx-talk
