Building From Source

Building from tarball

ddcutil can be built from its tarball in the usual way. Unpack the tar file, change to its directory, and issue the commands: 

# autoreconf --force --install 
# ./configure
# make
# sudo make install

configure options

The configure script has several custom options. Some reflect features under development, or tools used for development. The publicly supported options are:

Option Default Purpose
--enable-usb yes Build with support for USB connected monitors. Setting --disable-usb reduces size and package requirements. (Default is --enable-usb.)
--enable-drm yes Build with libdrm. Provides enhanced diagnostics, and is required for libddcutil to watch for hotplug events. Setting --disable-drm reduces size and package requirements. (Default is --enable-drm.)
--enable-lib yes Build the shared library. (Default is --enable-lib.)
--enable-asan no Build for execution with the Google Address Space Sanitizer.
--enable-envcmds yes Controls whether commands environment and usbenvironment are included.
--enable-udev yes Controls whether udev is used.
--enable-syslog yes Controls whether messages are written to the system log (Default is --enable-syslog.)
--enable-install-lib-only no Build and install only the shared library. Simplifies installation of an earlier version of libddcutil.

Notes:
- Option --disable-envcmds forces --disable-drm and --disable-x11

Required packages

Because of the variation among distributions, only general guidelines can be given for ddcutil prerequisites. Ultimately, you'll have to try to build ddcutil and see what breaks.

ddcutil requires the following packages for both building and execution (TO BE UPDATED):

  • i2c-tools
  • glib-2.0 (Note: glib-2.0 can be packaged with different names, e.g. libglib2.0-0, and may entail installing multiple packages.) Minimum version: 2.32
  • libgudev (e.g. libgudev1)
  • libusb-1.0 (e.g. libusb-1.0-0) Minimum version 1.0.15
  • libudev (e.g. libudev1)
  • libdrm2 Minimum version: 2.4.16
  • libjansson Minimum version 2.0.0
  • libxrandr2
  • hwdata

On most platforms, development related files (e.g. headers files) are in separate packages having a "-dev" or similar suffix in their names. ddcutil needs development packages for:

  • libc6 (e.g. libc6-dev)
  • glib2.0 (e.g. libglib2.0-0)
  • libusb (e.g. libusb-1_0-devel, libusb-1.0-0-dev)
  • udev or systemd (udev may be part of systemd, e.g. libudev-devel, libudev-dev)
  • xrandr (e.g. libxrandr-dev)
  • libdrm2 (e.g. libdrm-devel)
  • libjansson (e.g. libjansson-dev)

On older versions of Ubuntu, the i2c.h header file is found in a separate package.
If the following package exists, it is required to build ddcutil.

  • libi2c-dev

However, as of libi2c 4.0, i2c.h is no longer part of this package.

Error messages from configure regarding missing packages can be misleading. If configure complains that a package is not found but it seems to be installed, it's likely that the associated development package (with a suffix like "-dev") needs to be installed.

Building requires that the core build files be installed (e.g. the files listed in build-essential on Ubuntu) and also the pkg-config system.

  • pkg-config

Wnen make install is used, files are normally written to subdirectories of /usr/local. Some distributions include these subdirectories in the relevant paths, others do not. In particular, it may be necessary to copy source file /data/usr/lib/udev/rules.d/60-ddcutil.rules to directory /etc/udev/rules.d.

Building from git

The git repository for ddcutil is here

  • Building ddcutil from git requires that the autotools related packages be installed.
    The exact packages vary from distribution to distribution. On Ubuntu, these include:

    • autoconf, Minimum version: 2.50
    • automake, Minimum version: 1.13
    • autotools-dev
    • libtool
    • m4

To configure the build, change to the main ddcutil directory and execute the file: 

# ./autogen.sh

Or issue the individual commands: 

# aclocal
# autoheader
# autoconf
# automake

Then to configure, build, and install ddcutil: 

# ./configure
# make
# sudo make install

Shared library configuration

By default, command "sudo make install" installs the shared library files (libddcutil.so.n.n and symbolic links) in directory /usr/local/lib. In order to be available, command ldconfig must be run and it must find the shared library file. "sudo make install" automatically calls ldconfig after installing the library. For ldconfig to find the file, directory /usr/local/lib should be in a file in /etc/ld.so.conf.d. This is the case in Ubuntu.

For further details, see: Shared Library Configuration

Common issues:

  • If you see a message "required file './ltmain.sh.' not found", run libtoolize (See https://www.gnu.org/software/automake/manual/html_node/Error-required-file-ltmain_002esh-not-found.html)
  • May get the following warning when running automake
src/Makefile.am:38: warning: compiling 'cmdline/cmd_parser_aux.c' in subdir requires 'AM_PROG_CC_C_O' in 'configure.ac'

This is an autotools versioning issue. It appears that this warning can be ignored.

TO DO: add notes on other warnings that can be ignored

Development configuration options.

There are several configure options that exist for developing ddcutil. They are listed here for completeness, and should be left disabled.

  • --enable-callgraph
  • --enable-cffi
  • --enable-cython
  • --enable-doxygen
  • --enable-failisim
  • --enable-gobject-api
  • --enable-swig
  • --enable-testcases

Building ddcui

For notes on building ddcui, see Building ddcui