From Linux Man Pages
depmod -- program to generate modules.dep and map files.
SYNOPSIS
depmod [-b basedir] [-e] [-F System.map] [-n] [-v] [version] [-A ]
depmod [-e] [-FSystem.map] [-n] [-v] [version] [filename ...]
DESCRIPTION
Linux kernel modules can provide services (called "symbols") for other modules to use (using EXPORT_SYMBOL in the
code). If a second module uses this symbol, that second module clearly depends on the first module. These
dependencies can get quite complex.
depmod creates a list of module dependencies, by reading each module under /lib/modules/version and determining
what symbols it exports, and what symbols it needs. By default this list is written to modules.dep in the same
directory. If filenames are given on the command line, only those modules are examined (which is rarely useful,
unless all modules are listed).
If a version is provided, then that kernel version's module directory is used, rather than the current kernel
version (as returned by "uname -r").
depmod will also generate various map files in this directory, for use by the hotplug infrastructure.
OPTIONS
-b basedir --basedir basedir
If your modules are not currently in the (normal) directory /lib/modules/version, but in a staging
area, you can specify a basedir which is prepended to the directory name. This basedir is stripped
from the resulting modules.dep file, so it is ready to be moved into the normal location.
-e --errsyms
When combined with the -F option, this reports any symbols which a module needs which are not supplied
by other modules or the kernel. Normally, any symbols not provided by modules are assumed to be pro-
vided by the kernel (which should be true in a perfect world).
-F --filesyms System.map
Supplied with the System.map produced when the kernel was built, this allows the -e option to report
unresolved symbols.
-n --dry-run
This sends the resulting modules.dep, then the various map files, to standard output, rather than writ-
ing them into the module directory.
-A --quick
This option scans to see if any modules are newer the modules.dep file before any work is done: if not,
it silently exits rather than regenerating the files.
BACKWARDS COMPATIBILITY
This version of depmod is for kernels 2.5.48 and above. If it detects a kernel with support for old-style mod-
ules, or the version specified is before 2.5.48, it will attempt to run depmod.old in its place, so it is com-
pletely transparent to the user.
COPYRIGHT
This manual page Copyright 2002, Rusty Russell, IBM Corporation.
RELATED
modprobe(8), modules.dep(5), depmod.old(8)
CATEGORY