depmod(8) -- Linux man page
NAMEdepmod --- program to generate modules.dep and map files.
depmod [-b basedir] [-e] [-F System.map] [-n] [-v] [version] [-A ]
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
depmod creates a list of module dependencies,
by reading each module under
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
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").
- -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
provided by the kernel (which should be true in a
- -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 writing 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
This version of depmod is for kernels
2.5.48 and above. If it detects a kernel
with support for old-style modules, or the version specified is
before 2.5.48, it will attempt to run
depmod.old in its place, so it is completely
transparent to the user.