Automatic (on-demand) loading of modules.

Linux allows to load modules on demand, i.e. when they are actually needed for an application:

Old style:

/sbin/kerneld - external daemon

How it works: Based on SysV IPC (Inter-Proceess Connection) message protocol

/sbin/kerneld can also automatically remove modules.

New style:

Autoload support in the kernel (with recent kernels):

Select: Loadable modules support / kernel module loader

Source code: /usr/src/linux/kernel/kmod.c

Based on internal function request_module (char *module_name) - no need to
scan for a module. Cannot remove modules.

kmod does not unload modules (crond can be used for that)

Does my kernel provide kmod sypport?

ls /proc/sys/kernel/modprobe

If the file is found, it should contain the path to modprobe (/sbin/modprobe)
If file is not found. kernel module support is unavailable

N.B. kerneld related stuff has been removed from ipc/msg.c, therefore kerneld is not supported with the kernel version that includes internal module loader.

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