Clear Cache, Permission, Touch?

[stephensaw]

Hi,

 

I often see some guide that teach how to clear cache and set permission, sometimes touch after installing kext, what is the purpose of doing those thing?

 

Is doing all those action after installing kext will make any different? I mean if I installed some kext and reboot perfectly fine, and what if I go to clear cache, fix permission and touch thing, will it be by any chance spoil the install?

[^Andy^]

If you use something like kext utilty to install your kexts then you are likely to never need to do this manually.

There are times when you may need to do this manually howver such as when you can no longer boot due to having installed a dud kext for example.

[3.14r2]

Is doing all those action after installing kext will make any different? I mean if I installed some kext and reboot perfectly fine, and what if I go to clear cache, fix permission and touch thing, will it be by any chance spoil the install?

A kext with wrong permissions/ownership may not load. Caches cleaning IMO is not needed, cos' it is recreated automatically once a change is made to /S/L/E folder. However the above is not true for /Extra/Extensions. In that case caches must be recreated manually.

[stephensaw]

As ^Andy^ mention, one will need to clear cache when having problem to boot due to the newly installed kext (do this from boot flag I guess?) , is that mean literally there is not a need to do anything regarding cache, permission whether is on /S/L/E or /Extra/Extensions, right?

[3.14r2]

As ^Andy^ mention, one will need to clear cache when having problem to boot due to the newly installed kext (do this from boot flag I guess?)

Caches are use to shorten boot-up time by using a compiled (from kexts inside /S/L/E) set of all kexts that are needed to boot OS (kexts that are not needed for the OS to work, are not put to cache file). Instead of loading all kexts on each boot, OS X loads a compact fast loading cache file. Therefore if contents of /S/L/E folder is changed, a cache file must be recreated to reflect changes, or it might contain a kext(s) which is/are no longer present in /S/L/E (those an old cache file might still load a non-existent (in /S/L/E) kext).

 

is that mean literally there is not a need to do anything regarding cache, permission whether is on /S/L/E or /Extra/Extensions, right?

Not exactly. In SL (in Leopard a manual procedure is needed) cache file is recreated automatically if something is added/removed to/from /S/L/E. Therefore in case of /S/L/E, there is no need to recreate it.

 

But cache file made from /E/E IS NOT recreated automatically, as OS X is not aware of that location (it is not a part of OS X as Apple made it - it's pure hackintosh stuff). So if you use cache file for /E/E (I don't, cos' there are only few kexts) and made a change to /E/E contents, recreate cache file manually or some old kext will be loaded.

 

Now on permissions. If a kext has wrong permissions it should be fixed prior to creating cache manually or it may not be included to cache file (OS X can't use kexts with wrong permissions/ownership). There are some tools available to simplify the above procedure. These tools fixes permissions/ownership if needed.

[Hackintosh2000]

Hi,

 

I often see some guide that teach how to clear cache and set permission, sometimes touch after installing kext, what is the purpose of doing those thing?

 

Is doing all those action after installing kext will make any different? I mean if I installed some kext and reboot perfectly fine, and what if I go to clear cache, fix permission and touch thing, will it be by any chance spoil the install?

 

Use Kext Wizard and you won't have to mess with any of that.

[stephensaw]

Caches are use to shorten boot-up time by using a compiled (from kexts inside /S/L/E) set of all kexts that are needed to boot OS (kexts that are not needed for the OS to work, are not put to cache file). Instead of loading all kexts on each boot, OS X loads a compact fast loading cache file. Therefore if contents of /S/L/E folder is changed, a cache file must be recreated to reflect changes, or it might contain a kext(s) which is/are no longer present in /S/L/E (those an old cache file might still load a non-existent (in /S/L/E) kext).

 

Not exactly. In SL (in Leopard a manual procedure is needed) cache file is recreated automatically if something is added/removed to/from /S/L/E. Therefore in case of /S/L/E, there is no need to recreate it.

 

But cache file made from /E/E IS NOT recreated automatically, as OS X is not aware of that location (it is not a part of OS X as Apple made it - it's pure hackintosh stuff). So if you use cache file for /E/E (I don't, cos' there are only few kexts) and made a change to /E/E contents, recreate cache file manually or some old kext will be loaded.

 

Now on permissions. If a kext has wrong permissions it should be fixed prior to creating cache manually or it may not be included to cache file (OS X can't use kexts with wrong permissions/ownership). There are some tools available to simplify the above procedure. These tools fixes permissions/ownership if needed.

 

Wow, thanks for the clear explanation, I'm new to OS X, it helps