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But yet again, the big boys are moving in my direction, namely the ipad is single-tasking, yes i know the iphone was, but this is more like a pc.
Remember that single-tasking does not mean you can not listen to music, when browsing the net etc, as such things can be done in hardware.
Watch this space, to see if a modern PC can sell well with a single-tasking OS.

I haven't looked at the iPad yet, but...

Having only one application up front is not the same as single-tasking. Single-tasking would mean no background downloads, no appointment notifications, etc.

I would bet money that the iPod is merely limiting you to one "open" application at once (like, to translate to MS Windows terms, only one window in the task bar), but not to only one application running (i.e., only one icon in your notification area).

The iPhone wasn't single tasking. It only had one app in the foreground at any one time. Same holds for the iPad. Heck, both can even run ssh in the background.

You can do things such as listen to music while using an application, but you cannot, say, load an application which streams audio from an internet radio station and then send it to the background and browse the internet at the same time.

For things like the iPod it's okay, though even there it does get a little frustrating. For the iPad however, I think it may well be one of its most fundamental flaws. It means users won't be able to do basic things like browse the internet while reading a document/book/whatever - this is severely limiting in my opinion.

If however the iPad uses a modified version of the iPhone OS which allows multiple applications to run simultaneously, it may well end up being extremely popular and changing how users see computing in much the same way that the iPod changed how users saw music (and to a much lesser extent the iPhone and smart phones).

I already have a convertible tablet that runs Windows 7 so the appeal for an iPad isn't really there. And I have all my Windows applications and Microsoft have done a great job at making text input productive and intuitive with non table aware applications, and I can dock it and use it as my full-time desktop. The low price might make tablets a lot more accessible which is a good thing.

Dex wrote:But yet again, the big boys are moving in my direction, namely the ipad is single-tasking, yes i know the iphone was, but this is more like a pc.
Remember that single-tasking does not mean you can not listen to music, when browsing the net etc, as such things can be done in hardware.
Watch this space, to see if a modern PC can sell well with a single-tasking OS.

The iPhone OS is multitasking. It's only single tasking from an end user perspective.

Edit: I'm not usually this fail at reading threads. I should probably say something else.

I like the idea of a larger iphone type device but without multitasking and a few other things I can't really justify getting one.

Dex wrote:But yet again, the big boys are moving in my direction, namely the ipad is single-tasking, yes i know the iphone was, but this is more like a pc.
Remember that single-tasking does not mean you can not listen to music, when browsing the net etc, as such things can be done in hardware.
Watch this space, to see if a modern PC can sell well with a single-tasking OS.

Yea, I guess you showed us Dex. Oh wait. Minor clarifications

Dex wrote:But yet again, the big boys are moving in my direction, namely the ipad is single-tasking, yes i know the iphone was, but this is more like a pc.

The Ipad is like just a big iphone basically. It is not single tasking, it only shows 1 task at a time by the user interface however. It's basically just that you can't have more than 1 "window" open at a time. As everyone else said, you can listen to music and run ssh and other things in the background. The *only* reason the Ipod works the way it does is because having multiple applications open in the foreground would be impractical on the small screen.

Remember that single-tasking does not mean you can not listen to music, when browsing the net etc, as such things can be done in hardware.

What? Did you mean Single-Tasking *UI*? Last I checked DexOS was single tasking at the process level. So in order for you to browse the web and listen to music you would have to build a web browser and then build a media player into the web browser that ran on a separate thread. (Unless you add in your 1 prcoessor for 1 task nonsense)

Watch this space, to see if a modern PC can sell well with a single-tasking OS.

No, it can't. The Ipad is simply over coming the limitations of it's screen/tablet nature. If you had a huge 5000x5000px monitor, would you want absolutely all of it going to your Internet Explorer 6 web browser? Or would you actually want to be able to do more than 1 thing without pushing a button?

Why do you persist in annoying the OSDev community?

Combuster wrote:The iPhone wasn't single tasking.

Why do you talk about such a awesome thing in the past tense D= *runs home crying*

ucosty wrote:

Dex wrote:But yet again, the big boys are moving in my direction, namely the ipad is single-tasking, yes i know the iphone was, but this is more like a pc.
Remember that single-tasking does not mean you can not listen to music, when browsing the net etc, as such things can be done in hardware.
Watch this space, to see if a modern PC can sell well with a single-tasking OS.

The iPhone OS is multitasking. It's only single tasking from an end user perspective.

Edit: I'm not usually this fail at reading threads. I should probably say something else.

I like the idea of a larger iphone type device but without multitasking and a few other things I can't really justify getting one.

No, it's single tasking from a developer perspective too. Your app can't run in the background; it must be closed.

Theres a horrid work around for this in which the OS supports a "push notification" model whereby you can instruct it to ask a server to notify you when you get events, but it's a hack

(This excluses jail broken iPhones; the underlying OS fully supports it. Apple don't)

I just finished researching this iPad. and I see no reseon to hammer Dex even 1% as hard as you have.

news.com.au wrote:Multitasking - Is impossible on the iPad, which means you can only use one application at a time, reducing its functionality as a work computer to little more than a large iPhone.

Even IF it is multi tasking under the skin this says there is none.

Read for yourself. http://www.news.com.au/technology/ipad- ... 5824601392

It seems the iPad is single tasking from what they say.

And this says the iPhone is single tasking:

pcmag.com wrote: Apple had hit all the key notes—all but one, that is. What was missing? Multitasking.
Initially, I discounted the fact that the iPhone still can't do more than one thing at a time.

Read here: http://www.pcmag.com/article2/0,2817,2343380,00.asp

Dex wrote:I told you so

I don't own an iPhone so I can't comment. Windows CE and Mobile are multitasking in since you can have multiple programs running, yet single tasking from the GUI's perspective in that only one program takes up the entire screen at a time.

The Xbox 360 is also multitaskable to a certain extent. The system software (which includes Windows Live Messenger and a file downloader) is always present in the background.

What I don't understand is why (non-arcade) Xbox 360 games don't have an Exit option on their menus. You can quit by pressing the X so a system menu pops up then choose "return to Dashboard" (which is somewhat like using CTRL+ALT+Delete to close a program on Windows).

Coddy wrote:I just finished researching this iPad. and I see no reseon to hammer Dex even 1% as hard as you have.

news.com.au wrote:Multitasking - Is impossible on the iPad, which means you can only use one application at a time, reducing its functionality as a work computer to little more than a large iPhone.

Even IF it is multi tasking under the skin this says there is none.

That's the wrong definition of multitasking. The phone will still be checking and downloading email or playing music while you are running applications. The problem is that you can only do one thing at a time.

From an OSDev view it's still multitasking, but from a user's view it's not. news.com.au isn't going to offer the OS perspective, just that of the general public who actually use the thing without caring about what goes on inside.

pcmattman wrote:

Coddy wrote:I just finished researching this iPad. and I see no reseon to hammer Dex even 1% as hard as you have.

news.com.au wrote:Multitasking - Is impossible on the iPad, which means you can only use one application at a time, reducing its functionality as a work computer to little more than a large iPhone.

Even IF it is multi tasking under the skin this says there is none.

That's the wrong definition of multitasking. The phone will still be checking and downloading email or playing music while you are running applications. The problem is that you can only do one thing at a time.

From an OSDev view it's still multitasking, but from a user's view it's not. news.com.au isn't going to offer the OS perspective, just that of the general public who actually use the thing without caring about what goes on inside.

Yes, but this is important: Only Apple's apps can be backgrounded

MessiahAndrw wrote:I don't own an iPhone so I can't comment. Windows CE and Mobile are multitasking in since you can have multiple programs running, yet single tasking from the GUI's perspective in that only one program takes up the entire screen at a time.

Symbian is similar, except it is also multitasking to it's users: Running apps get an icon next to them in menus, and there is a running process list (Generally accessed by holding down the menu button)

The Xbox 360 is also multitaskable to a certain extent. The system software (which includes Windows Live Messenger and a file downloader) is always present in the background.

What I don't understand is why (non-arcade) Xbox 360 games don't have an Exit option on their menus. You can quit by pressing the X so a system menu pops up then choose "return to Dashboard" (which is somewhat like using CTRL+ALT+Delete to close a program on Windows).

The case of the 360 and PS3 is interesting, in that the dashboard/XMB runs in the same address space as the game. Though in many regards you could say that, at least in the XMB's case, it's a part of the OS (Both the game and XMB are the same logical process under the single tasking hypervisor)

Owen wrote:

The Xbox 360 is also multitaskable to a certain extent. The system software (which includes Windows Live Messenger and a file downloader) is always present in the background.

What I don't understand is why (non-arcade) Xbox 360 games don't have an Exit option on their menus. You can quit by pressing the X so a system menu pops up then choose "return to Dashboard" (which is somewhat like using CTRL+ALT+Delete to close a program on Windows).

The case of the 360 and PS3 is interesting, in that the dashboard/XMB runs in the same address space as the game. Though in many regards you could say that, at least in the XMB's case, it's a part of the OS (Both the game and XMB are the same logical process under the single tasking hypervisor)

I know 360 games run in ring 0, but I'm not sure if they run in the same address space. If that were true then it would be more preferable to let the game clean up rather than forcefully kill it. Also Xbox Live Arcade games have an exit option so I wouldn't say it's not supported by the OS.

Whether a device like the iPad should support multitasking from the user's perspective is purely a UI debate.

Whether an OS should abandon a multi-process architecture just because its UI is going to be single-tasking is an entirely different debate.

I will only point out that it's much easier to change a multi-process single-tasking OS (like iPhone OS) to do multi-tasking than it is to change a single-process OS like DOS to do multi-tasking.