/************************************************************************* * Android udev/dev Device Node Permissions * Note: * Now the Linux System device node permissions are generally through dynamic configuration, has not found the specific * where the configuration of the instructions, this time in the reference books found ueventd.rc is used to do this thing. * 2016-5-14 Shenzhen Nanshan Ping Shan village Zengjianfeng ************************************************************* ***********/One, reference document: Embedded Android https://www.google.co.id/url?sa=t&rct=j&q=&esrc=s&source=web&cd=5&ved= 0ahukewiwwcrbqtjmahwdppqkhdhjbroqfgg5maq&url=http%3a%2f%2fwww.staroceans.org%2fkernel-and-driver%2f% 255bembedded.android (2013.3)%255d. Karim.yaghmour.pdf&usg=afqjcnhe5ey14eglqxgmopp-pgn510algasecond, the original text:1. Page: - 2. Content: Udev events as I explained earlier, access to devicesinchLinux isDone through nodes within The/dev directory. In the old days, Linux distributions would ship with thousands of entriesinchThat's directory to accommodate all possible device configurations. Eventually, though, a few schemes were proposed to make the creation of such nodes dynamic. For some time now, the systeminchUse have been udev, which relies on runtime events generated by the kernel every time hardware isAdded or removed fromThe system. In most Linux distributions, the handling of Udev hotplug events isDone by the UDEVD daemon. In Android, these events is handled by the UEVENTD daemon built asPart of Android ' s init and accessed through a symbolic link from/sbin/ueventd To/init. To know which entries to createinch/dev, Ueventd relies on the/ueventd.rc and/ueventd.<device_name>. rc files. Summary: Before encountering the need to modify the permissions, and so on, is generally in the init.rc to modify, at that time feel very strange, because there will be special to the device node set permissions files, there is obviously not, but also did not find the exact place, and now finally found the basis.
Android Udev/dev Device Node permissions