macOS Recognizing device connection

[pithhelmet]

Hello everyone,

Not really a programming question, but....

How does an application (itunes helper) sense when a device is connected?

I've put network monitor, port watchers, and netbios watchers on my system, but I cannot figure out how the itunes system picks up that a iXXX device is connected....

does anyone have any ideas?

thanks
tony

 

[kainjow]

You can use IOKit http://developer.apple.com/mac/libr....html#//apple_ref/doc/uid/TP30000379-BABEACCJ

Edit: well that link provides code, but if you're looking for a non-programming way to do it, there may be some apps out there that wrap that functionality into a UI, but I'm not aware of any directly.

 

[chown33]

If you run System Profiler.app, located in Utilities, and connect then disconnect your iPod, does it show up in the list of USB devices?

You will need to choose Refresh from System Profiler's View menu. It does not update its display automatically.

If the iPod shows up as a USB device, then the answer lies in how USB devices identify themselves when plugged in. USB in Mac OS X is handled through IOKit, as kainjow already noted.

The actual signals on the USB bus are defined by the USB standard. See this description:
http://en.wikipedia.org/wiki/Universal_Serial_Bus#Signaling

The relevant paragraphs begin at:

The host includes 15 kΩ pull-down resistors on each data line​

 

[robbieduncan]

Edit: well that link provides code, but if you're looking for a non-programming way to do it, there may be some apps out there that wrap that functionality into a UI, but I'm not aware of any directly.

There's Hardware Growler for one...