Wikipedia:Reference desk/Archives/Computing/2017 June 8

From Wikipedia, the free encyclopedia
Computing desk
< June 7 << May | June | Jul >> June 9 >
Welcome to the Wikipedia Computing Reference Desk Archives
The page you are currently viewing is an archive page. While you can leave answers for any questions shown below, please ask new questions on one of the current reference desk pages.


June 8[edit]

windows 10 and annoying taskbar behaviour[edit]

hi all, another win 10 irritation ... on the taskbar, when I have eg. two different instances of firefox running, I can't get two different icons on the taskbar. I have to click the single icon, then it shows me two screens, then I have to click the right one. This irritates the heck out of me. How do I change it? Better, can I get back the whole vista taskbar, which has the title of the open window? Win 10 is mostly an improvement, but I worry that some weirdos have taken over the look and feel (Cortana etc). IBE (talk) 02:17, 8 June 2017 (UTC)[reply]

See if this helps. Look for Taskbar Buttons options under Taskbar properties (right mouse click on the Taskbar). manya (talk) 06:22, 8 June 2017 (UTC)[reply]
Excellent, should have done more googling first, sorry there ;(, otoh, I have been consuming so much time with so many related windows 10 things, that I was pretty much going mad. At least that's the excuse I'm using, cheers, IBE (talk) 06:28, 8 June 2017 (UTC)[reply]

docker layers - deleted files[edit]

I can see how docker can overlay "layers" of files if you add or change a file in a newer layer that one is seen. How does Docker manage if you remove a file in a later layer? -- Q Chris (talk) 09:27, 8 June 2017 (UTC)[reply]

"Each layer has an archive of the files which have been added, changed, or deleted relative to its parent layer" - so it uses a union mount (or, as there can be many layers, a series of concentric union mounts). -- Finlay McWalter··–·Talk 10:36, 8 June 2017 (UTC)[reply]
Hmm, on thinking about it, probably not concentric mounts, that's overcomplicating it. -- Finlay McWalter··–·Talk 11:54, 8 June 2017 (UTC)[reply]
As to the matter of deletion specifically, The Design and Implementation of the 4.4BSD Operating System by McKusick et al. (p236) has a nice explanation "The tricky part ... is handling the removal of files that reside in a lower layer. Since the lower layers cannot be modified, the only way to remove a file is to hide it by creating a whiteout directory entry in the top layer ... If the kernel finds a whiteout entry while searching for a name, the lookup is stopped and the 'no such file' error is returned." I think most subsequent union filesystem implementations work the same as the early BSD one described there. -- Finlay McWalter··–·Talk 10:46, 8 June 2017 (UTC)[reply]