From b01a12a13531c56a336a399456cb71709bb1a549 Mon Sep 17 00:00:00 2001 From: Michael Opdenacker Date: Thu, 27 Apr 2023 17:30:05 +0200 Subject: manuals: expand init manager documentation - Add details about INIT_MANAGER Correct the fact that "none" currently generates an image with "sysvinit", at least on Poky. This behaviour should probably be changed. - Expand the "Selecting an Initialization Manager" section. - Stop mentioning "rescue image" generation, as this is not detailed anywhere else. (From yocto-docs rev: fd99f2753b50b7ad6133b787b90331fcb3a35152) Signed-off-by: Michael Opdenacker CC: Paul Eggleton Signed-off-by: Richard Purdie --- documentation/ref-manual/variables.rst | 31 ++++++++++++++++++++++++------- 1 file changed, 24 insertions(+), 7 deletions(-) (limited to 'documentation/ref-manual') diff --git a/documentation/ref-manual/variables.rst b/documentation/ref-manual/variables.rst index 01b710199d..afb1fe9924 100644 --- a/documentation/ref-manual/variables.rst +++ b/documentation/ref-manual/variables.rst @@ -3959,16 +3959,33 @@ system and gives an overview of their function and contents. :term:`INIT_MANAGER` Specifies the system init manager to use. Available options are: - - ``sysvinit`` - System V init (default for poky) - - ``systemd`` - systemd - - ``mdev-busybox`` - mdev provided by busybox - - ``none`` - no init manager + - ``sysvinit`` + - ``systemd`` + - ``mdev-busybox`` + - ``none`` + + With ``sysvinit``, the init manager is set to + :wikipedia:`SysVinit `, the traditional UNIX init + system. This is the default choice in the Poky distribution, together with + the Udev device manager (see the ":ref:`device-manager`" section). + + With ``systemd``, the init manager becomes :wikipedia:`systemd `, + which comes with the :wikipedia:`udev ` device manager. + + With ``mdev-busybox``, the init manager becomes the much simpler BusyBox + init, together with the BusyBox mdev device manager. This is the simplest + and lightest solution, and probably the best choice for low-end systems + with a rather slow CPU and a limited amount of RAM. + + With ``none``, the init manager is also set to ``sysvinit``. This is the + default setting in OpenEmbedded-Core. This option also selects the + :wikipedia:`udev ` device manager. More concretely, this is used to include ``conf/distro/include/init-manager-${INIT_MANAGER}.inc`` into the global - configuration. You can have a look at the ``conf/distro/include/init-manager-*.inc`` - files for more information, and also the - ":ref:`dev-manual/init-manager:selecting an initialization manager`" + configuration. You can have a look at the + :yocto_git:`meta/conf/distro/include/init-manager-*.inc ` + files for more information, and also the ":ref:`init-manager`" section in the Yocto Project Development Tasks Manual. :term:`INITRAMFS_DEPLOY_DIR_IMAGE` -- cgit v1.2.3-54-g00ecf