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- [Narrator] Where are these cool

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loadable kernel module files?

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What do they look like?

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Well, modules are installed into a directory

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under /lib/modules

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and under there should be a subdirectory

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for each kernel version you have installed.

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So the modules will be in the subdirectory

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for the kernel version they go with.

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Also, by the way,

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the directory has not only kernel module files,

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but it has configuration files having to do

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with those modules that include information, for example,

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about dependencies between modules.

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So module files are files, they should have a unique name.

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Now they can be in any directory underneath there,

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but generally there's some organization to it.

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There's sub directories under there

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for different kinds of modules.

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And we'll look at the mod probe command later.

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It finds the modules there.

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And remember, you only load modules into your kernel

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that were built for your kernel.

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And that means not only the version of your kernel,

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but how your kernel was configured.

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So be careful about that.

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And also remember, modules run in kernel mode

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with all the privileges.

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So it's somewhat of a dangerous thing to be

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writing custom modules or certainly loading the module

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that you got from someplace, right?

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This is kernel level code.