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ferg · Apr 11, 2007, 04:24 PM

Can OSX run two instances of the same application at the same time like windows can?

I know I can run them in different users, but cannot figure out how to open a single app twice in one user. Not real important, just a friend is doing it on windows and was wondering if the Mac could do it too.

Thanks.

olePigeon · Apr 11, 2007, 04:45 PM

Not that I know of. When would you want to to do that, though?

Sherman Homan · Apr 11, 2007, 04:45 PM

Why?
What would you gain?

ferg · Apr 11, 2007, 04:47 PM

Just curious, I never saw a need for it, but my mate was running 2 instances of World of Warcraft on his PC with his two accounts, and he asked if Macs could do that.

peeb · Apr 11, 2007, 05:13 PM

Well, you could do it in two user accounts, and use fast user switching....

ferg · Apr 11, 2007, 05:43 PM

yeah can do that, but he had them both up on screen at once, looked pretty cool.

Mithras · Apr 11, 2007, 05:44 PM

Yes, it can be done, via the Terminal. It's generally not a very good idea, though, since it can cause unexpected things to happen to preference files and the like.

olePigeon · Apr 11, 2007, 05:46 PM

If he's looking for a pissing contest, then load up WoW on your Mac, then run Parallels or VMWare with multiple instances of Windows running multiple instances of World of Warcraft.

TheoCryst · Apr 11, 2007, 06:05 PM

Originally Posted by olePigeon

If he's looking for a pissing contest, then load up WoW on your Mac, then run Parallels or VMWare with multiple instances of Windows running multiple instances of World of Warcraft.

slpdLoad · Apr 11, 2007, 06:09 PM

Depending on what app it is, you can just duplicate the .app and double click on both copies.

mduell · Apr 11, 2007, 07:24 PM

You can't do that in all apps in Windows.

Heck, with Windows Movie Maker, you can't even open 2 instances as separate users, much less the same user.

peeb · Apr 11, 2007, 08:06 PM

Yes, you could try to install it twice, in different places. Some apps will allow that. Running it twice depends more on the app, and whether it supports multiple instances of itself, than the OS.

pixelbaker · Apr 11, 2007, 08:30 PM

I would be interested in doing this using DVD2OneX when I've got several jobs to do and I'd like to do them simultaneously, basically queuing them so I can set it and forget it. Anyone have any experience with that?

Chuckit · Apr 11, 2007, 10:29 PM

This can be done, but depending on the program it might not work right. Some programs are written with the assumption that they'll be the only instance running. Most programs, though, it works fine. You can either duplicate the app or launch it manually from the Terminal (e.g. /Applications/TextEdit.app/Contents/Resources/MacOS/TextEdit).

mfbernstein · Apr 12, 2007, 08:55 AM

Don't need to use the shell. Open the first instance of the program normally. To open the second instance, right-click the application, select 'Show Package Contents'. Navigate in the Finder to Contents then MacOS. Double-click Applicationname inside MacOS.

It'll launch a terminal automatically, as well as a second instance of the program.

(I use this regularly with SuperDuper when I want to back up to two disks at once).

ferg · Apr 12, 2007, 01:33 PM

Originally Posted by mfbernstein

Don't need to use the shell. Open the first instance of the program normally. To open the second instance, right-click the application, select 'Show Package Contents'. Navigate in the Finder to Contents then MacOS. Double-click Applicationname inside MacOS.

It'll launch a terminal automatically, as well as a second instance of the program.

(I use this regularly with SuperDuper when I want to back up to two disks at once).

Well, I'll be, that works...thx!

Thorzdad · Apr 12, 2007, 02:59 PM

Once I discovered I was running two instances of Adobe Illustrator CS at the same time. I have no idea how I did it, though. All I can figure is that I somehow launched it from my main HD and then launched it from the Firewire HD I use for backup. It's just a guess, but I had them both running at the same time in the same account.

Mediaman_12 · Apr 12, 2007, 06:15 PM

Another point is that Windows can do this, because of it's retarded window=application concept. Newer apps use various ways round this, but if you open 2 documents in a pre 2003 version of Word, that's 2 instances of the full application.
The Mac OS never had this 'problem' as applications and open documents where never tied together.

Macola · Apr 13, 2007, 03:49 PM

Retarded is right. I remember recently trying to see if the brightness keys (F1) on my MacBook would work in XP, and before I had realized it, there were 45 instances of the Help viewer open...

ferg · Oct 3, 2007, 09:16 AM

Ok So I have been able to run 2 even 3 instances of WoW on my Dual1.8 G5 with 1.5gig of ram with very little slowdown(within reason) and it has been quite handy at times with my two accounts.

A friend with two accounts recently tried it on his iMac, the white version just before they went aluminum, so I am assuming a 2ghz Core2Duo with 2gig of ram. But just attempting to open a second instance of the game slows the machine to a crawl to the point of unresponsiveness forcing a hard restart. I had the Activity Viewer open and it shows each instance almost battling for the processors, bouncing back from 116% usage for one and 50% usage on the other(not sure how that is possible), to 50/50% but it seems it is struggling to do anything.

I would have thought on the much newer machine(mine is pushing 4years old and his is maybe 5-6 months), would blow mine away in this, he has more RAM, more processor speed, newer graphics card(both running at 256meg though). The only difference I can tell would be mine is 64bit and his is 32bit processors, but I wouldn't have thought that would make a difference.

BLAZE_MkIV · Oct 3, 2007, 10:28 AM

I believe if you have 2 copies if the app you can launch it twice, try it with text edit or something small. This obviously becomes an issue if the app is large like WOW.

ferg · Oct 3, 2007, 10:31 AM

Oh, I have run 3 instances of WoW with no prob on my G5, but on his new iMac, which in all aspects appears better equipped, it grinds his machine to a halt.

mdc · Oct 3, 2007, 10:59 AM

Originally Posted by Mediaman_12

Another point is that Windows can do this, because of it's retarded window=application concept. Newer apps use various ways round this, but if you open 2 documents in a pre 2003 version of Word, that's 2 instances of the full application.
The Mac OS never had this 'problem' as applications and open documents where never tied together.

At work I have a text file on my desktop that I use to keep notes. Windows will let me open that file as many times as I want. I sometimes have 3 different notepads open with this same document and each has different data. I then have to manually reconcile the data into 1 text file before I save it.

Retarded? Definitely.

Mac User #001 · Oct 3, 2007, 02:29 PM

I've needed, or rather wanted, to use it in Windows. There's an app I use that won't let two of its documents open at once, so I just open the application twice.

ferg · Oct 3, 2007, 02:35 PM

Originally Posted by ferg

Ok So I have been able to run 2 even 3 instances of WoW on my Dual1.8 G5 with 1.5gig of ram with very little slowdown(within reason) and it has been quite handy at times with my two accounts.

A friend with two accounts recently tried it on his iMac, the white version just before they went aluminum, so I am assuming a 2ghz Core2Duo with 2gig of ram. But just attempting to open a second instance of the game slows the machine to a crawl to the point of unresponsiveness forcing a hard restart. I had the Activity Viewer open and it shows each instance almost battling for the processors, bouncing back from 116% usage for one and 50% usage on the other(not sure how that is possible), to 50/50% but it seems it is struggling to do anything.

I would have thought on the much newer machine(mine is pushing 4years old and his is maybe 5-6 months), would blow mine away in this, he has more RAM, more processor speed, newer graphics card(both running at 256meg though). The only difference I can tell would be mine is 64bit and his is 32bit processors, but I wouldn't have thought that would make a difference.

Just bumping my question as to why it would work fine with WoW on a 4yr old G5 vs a 6mo old iMac. There is no doubt it works, I can do it with any app, I just was wondering what is weak on the new iMac that makes it struggle, only thing I can surmise is 32bit vs 64bit, but I didnt think that would be an issue.

esXXI · Oct 5, 2007, 04:54 AM

Perhaps your friend had a lot of addons and/or WoW doesn't like running two of the same application on intel Macs. I found it just easier to duplicate the WoW folder to avoid any hassles.

angelmb · Oct 5, 2007, 07:19 AM

A friend of me sent me a link to a mp4 file where you can see his Quad G5 running not two or three instances of the same app at one but 30 !!

That was a SNES emulator, every one of them was running a ROM no other emulator was…

oh, found it…
MEGAUPLOAD - The leading online storage and file delivery service

ferg · Nov 4, 2007, 01:34 PM

Originally Posted by esXXI

I found it just easier to duplicate the WoW folder to avoid any hassles.

Just an update, this works on the Intel Imac. Thanks!