KEXTCACHE(8) BSD System Manager's Manual KEXTCACHE(8)
NAME
kextcache -- creates or updates kext caches
SYNOPSIS
kextcache [-a arch] [-c kernel_cache_filename] [-e] [-F] [-h] [-k] [-K kernel_filename] [-l | -L] [-m mkext_filename] [-n | -N] [-r]
[-s | -S] [-t] [-v [1-6]] [-z] [kext_or_directory] ...
DESCRIPTION
The kextcache program creates or updates kext caches, which are used to speed up kext loading operations and to prepare kexts for inclusion
in such media as device ROM.
There are three kinds of kext cache. The first is the mkext cache, which contains the info dictionaries and binary files for an arbitrary
set of kexts. Mkext caches are used during early system startup to load drivers essential to mounting the root filesystem and providing
basic hardware services. They're also used to package drivers in device ROM. To create an mkext cache use the -m option.
The second type of cache is the kext repository cache, which contains the info dictionaries for all the kexts in a single repository direc-
tory, including their plugins, in a file with a .kextcache extension. A repository cache speeds the startup of tools such as kextload(8) and
kextd(8). A repository cache must exist alongside its repository directory for the kext tools to find and use it. The kext tools normally
build or update repository caches as needed. To create or update a kext cache use the -k option.
The third type of cache is the kernel cache, which contains the kernel code, linked kext code, and info dictionaries for an arbitrary set of
kexts. Having the kernel code and kexts already linked speeds the startup of tools such as kextload(8) and kextd(8). To create or update a
kernel cache use the -c option.
kextcache accepts these arguments and options:
kext_or_directory
A kext bundle or a repository directory containing kexts to add to the cache. When using the -m option only, any number may be
specified. When using the -k option, only a single directory may be named.
-a arch Include in an mkext archive only kexts whose executable files contain code for the given arch, stripping the binaries before inclu-
sion. If multiple -a options are used, a fat file will be created containing multiple mkext archives that are thinned for each of
the specified architectures.
-c kernel_cache_filename
The name of the kernel cache file to create. If none is specified, a cache file is created in the /Sys-
tem/Library/Caches/com.apple.kernelcaches/ folder.
-e This option is a convenience to update the mkext cache for the /System/Library/Extensions folder.
-F Fork a child process and exit immediately. This allows a cache update during system startup to continue without delaying startup.
-h Extended usage statement
-k Create or update the kext cache for any repository directories specified.
-K kernel_filename
The name of the kernel file to use as the base of a kernel cache file (default is /mach_kernel).
-l Specifies that for directory arguments, only extensions required for local disk boot be included in an mkext cache. Kexts explic-
itly named on the command line are included unconditionally; to apply this restriction to all kexts, use the -L option. May be com-
bined with the -n, -N, -s, or -S options to archive network-root and safe boot extensions as well.
-L Specifies that only extensions required for local disk boot be included in an mkext cache. To apply this restriction only to repos-
itory directories, use the -l option. May be combined with the -n, -N, -s, or -S options to archive network-root and safe boot
extensions as well.
-m mkext_filename
The name of the mkext cache file to create.
-n Specifies that for directory arguments, only extensions required for network boot be included in an mkext cache. Kexts explicitly
named on the command line are included unconditionally; to apply this restriction to all kexts, use the -N option. May be combined
with the -l, -L, -s, or -S options to archive local-root and safe boot extensions as well.
-N Specifies that only extensions required for network boot be included in an mkext cache. To apply this restriction only to reposi-
tory directories, use the -n option. May be combined with the -l, -L, -s, or -S options to archive local-root and safe boot exten-
sions as well.
-r Include all kexts that have been loaded by the machine running this command during this boot. This include kexts loaded and later
unloaded.
-s Specifies that for directory arguments, only extensions required for safe boot be included in an mkext cache. Kexts explicitly
named on the command line are included unconditionally; to apply this restriction to all kexts, use the -S option. May be combined
with the -l, -L, -n, or -N options to archive local- and network-root extensions as well.
-S Specifies that only extensions required for safe boot be included in an mkext cache. To apply this restriction only to repository
directories, use the -s option. May be combined with the -l, -L, -n, or -N options to archive local- and network-root extensions as
well.
-t Perform all possible tests on the named kext(s) and indicate whether the kext is loadable (and therefore eligible for inclusion in
the cache), or if not, what problems it has. Note that tests are performed in three stages, validation, authentication, and depen-
dency resolution; a failure at any stage can make tests in further stages impossible. Thus, a kext with validation failures may
have unreported authentication problems or missing dependencies.
-v [1-6]
Verbose mode; print information about the kext scanning and loading process. Higher levels of verbosity include all lower levels.
With this program only verbose levels 1-3 are useful. The levels of verbose output are these:
1 prints basic kext scanning and archiving information
2 prints basic compression information
3 prints detailed kext scanning information; also uncompresses mkext cache entries to make sure they do so without error
4 prints basic information on every kext encountered
5 prints detailed information on every kext encountered
6 prints detailed load information (not applicable)
A kext can also specify verbose printing for just itself using the OSBundleDebugLevel top-level info dictionary property. Its val-
ues are 1 and 2, for basic and detailed information, respectively.
-z Don't authenticate kexts. This option is for convenience in building archive and cache files. Mkext archives and kext repository
caches must have proper ownership (root:wheel) and permissions (0644) in order to be used by the system.
-- End of all options. Only kext or directory names follow.
DIAGNOSTICS
kextcache exits with a zero status upon success. Upon failure, it prints an error message and exits with a nonzero status. When the -F
option is used, however, kextcache exits with a nonzero status only if the fork(2) operation fails.
SEE ALSO
kextd(8), kextload(8), kextstat(8), kextunload(8)
BUGS
Upon encountering a kext with validation errors, kextcache typically prints an error message about that kext, even if it isn't involved in
the cacheing request.
Darwin April 8, 2002 Darwin