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May 27

Linux, file created on?

Why do linux files do not have a creation date metainformation? OsmanRF34 (talk) 01:18, 27 May 2012 (UTC)[reply]

They can, but why should they? ¦ Reisio (talk) 03:51, 27 May 2012 (UTC)[reply]

All versions of ext have create, modify, and access date metadata. Shadowjams (talk) 03:45, 28 May 2012 (UTC)[reply]

Wrong. Traditional unix filesystems have atime, mtime, and ctime. Lots of people guess that ctime stands for "creation time", and then that guess turns in to a solid belief over a long period of failing to read any proper documentation, and that solid belief sometimes becomes an authoritative pronouncement reinforcing other people's bad guesses... Actually ctime stands for "change time" and it's updated whenever any attribute of the file changes. Among native Linux filesystems, ext4 has a creation time field, but ext3 and earlier don't. Just see the articles ext3 and ext4, where it says "Dates recorded".

As for why it took so long, I don't know, but it might have been a chicken/egg problem. Even now, with ext4 recording the creation times, it's hard to actually look at them, since 40 years of unix tools and programming languages have been built around the assumption that the original 3 timestamps are the only ones that exist. 98.226.12.79 (talk) 04:50, 28 May 2012 (UTC)[reply]

ctime used to stand for "creation time". Richie & Thompson's 1974 paper "The UNIX Time-Sharing System" says (in section IV) that an inode records "time of creation, last use, and last modification". Similarly the 1971 Unix system manual's section on the stat(2) call shows it yielding 4 bytes for "creation time" (ctime) and 4 for "modification time" (so we're before the age of atime). There's nothing in the brief descriptions of inode-altering calls like chown(2) and chmod(2) that says these change the ctime. So at some point after Unix defined ctime someone decided that meta-calls like chown should change the ctime, and thus they had to back-change what the abbreviation means to the rather mealymouthed "change time". This blog posting puts the change at around UNIXv7. I'll bet the change happened when someone was writing an incremental tape backup program and complained that they needed to capture permissions changes, but didn't want to have to write a whole file to the tape whenever it was merely chmod-ed. Apart from that use (which only makes sense on sequential media like tape; rsync's method make much more sense when one has random-access backup media) I'm rather lost to think of a useful application for ctime. Happily many modern unixen have taken a "better good than POSIX" approach to atime (cf Stat (Unix)#Solutions); perhaps a ctimecreate option for mount would make sense. -- Finlay McWalterჷTalk 14:09, 28 May 2012 (UTC)[reply]

I'm going to update Stat (system call) a little bit to reflect some of what Finlay has said. Shadowjams (talk) 18:00, 28 May 2012 (UTC)[reply]

To my mind there's a lot of stuff in Stat (system call) that should be in inode, including almost all of the extensive atime discussion (and inode is where I'd expect details about ctime worked and works). These data are held in the inode and changed by a variety of syscalls; stat is merely the means by which we see them. -- Finlay McWalterჷTalk 18:12, 28 May 2012 (UTC)[reply]

Lyrics on phones

Can the Samsung SII display lyrics while a song plays? I wouldn't think so, but, just asking. --Sp33dyphil ©^hat_ontributions 09:35, 27 May 2012 (UTC)[reply]

Which version of Windows is Wine supposed to be?

OsmanRF34 (talk) 16:12, 27 May 2012 (UTC)[reply]

winecfg lets you set which version it tries to pretend to be. The docs say it defaults to Windows XP - but in practice it implements some subsystems from newer versions, and doesn't fully implement everything from older ones. -- Finlay McWalterჷTalk 16:20, 27 May 2012 (UTC)[reply]

Bluetooth on Win7 and Samsung Galaxy Phone

I am unable to connect to my phone using Bluetooth from my Win7 laptop. My phone connects ok, and the computer even notices that I have changed the name of the device, but when I try to transfer any files, it just tells me it can't find the device. I have been into Control Panel>Administrative Tools>Services, and everything appears to be running. Does anyone know what to do here? KägeTorä - (影虎) (TALK) 17:55, 27 May 2012 (UTC)[reply]

Not all Bluetooth stacks are equal, you might try http://www.broadcom.com/support/bluetooth/update.php or http://aps2.toshiba-tro.de/bluetooth/?page=download. ¦ Reisio (talk) 19:03, 27 May 2012 (UTC)[reply]

Thanks. My PC is a HP laptop with Win7. I have not been able to update the driver, and I think it just gets done automatically. So, basically, what you're saying is, my phone's Bluetooth and my PC's Bluetooth may not be compatible? That's annoying, because neither is my iPod's Bluetooth (which works only with iPhone and Mac computers). As I also don't have a USB cable for the phone, I have taken to sending all the files I want by email. Cheers, anyway. KägeTorä - (影虎) (TALK) 13:22, 28 May 2012 (UTC)[reply]

Not so much incompatible as much as your laptop may well not have even come with any stack (to speak of). If it doesn't have internal bluetooth this is a foregone conclusion, if it does it's probably something else. ¦ Reisio (talk) 20:59, 28 May 2012 (UTC)[reply]

Well, my laptop's Bluetooth worked with my old Sony Ericsson and works with my Android tablet. I'm surprised it won't work with my Galaxy phone (which is also Android)...... KägeTorä - (影虎) (TALK) 21:22, 29 May 2012 (UTC)[reply]

Twitter following

Occasionally, I find that somehow a load of people have somehow made me follow them on Twitter without me wanting to. It's bloody annoying. How can I stop this happening? Thank you. DuncanHill (talk) 18:50, 27 May 2012 (UTC)[reply]