diff options
Diffstat (limited to 'doc')
| -rw-r--r-- | doc/guix.texi | 26 | ||||
| -rw-r--r-- | doc/images/service-graph.dot | 5 |
2 files changed, 22 insertions, 9 deletions
diff --git a/doc/guix.texi b/doc/guix.texi index 74e0977db5..6ab98deef3 100644 --- a/doc/guix.texi +++ b/doc/guix.texi @@ -7589,8 +7589,11 @@ as arrows, a typical system might provide something like this: @image{images/service-graph,,5in,Typical service extension graph.} -At the bottom, we see the @dfn{boot service}, which produces the boot -script that is executed at boot time from the initial RAM disk. +@cindex system service +At the bottom, we see the @dfn{system service}, which produces the +directory containing everything to run and boot the system, as returned +by the @command{guix system build} command. @xref{Service Reference}, +to learn about the other service types shown here. @xref{system-extension-graph, the @command{guix system extension-graph} command}, for information on how to generate this representation for a particular operating system definition. @@ -7853,12 +7856,14 @@ Return true if @var{obj} is a service extension. At the core of the service abstraction lies the @code{fold-services} procedure, which is responsible for ``compiling'' a list of services -down to a single boot script. In essence, it propagates service -extensions down the service graph, updating each node parameters on the -way, until it reaches the root node. +down to a single directory that contains everything needed to boot and +run the system---the directory shown by the @command{guix system build} +command (@pxref{Invoking guix system}). In essence, it propagates +service extensions down the service graph, updating each node parameters +on the way, until it reaches the root node. @deffn {Scheme Procedure} fold-services @var{services} @ - [#:target-type @var{boot-service-type}] + [#:target-type @var{system-service-type}] Fold @var{services} by propagating their extensions down to the root of type @var{target-type}; return the root service adjusted accordingly. @end deffn @@ -7866,9 +7871,14 @@ type @var{target-type}; return the root service adjusted accordingly. Lastly, the @code{(gnu services)} module also defines several essential service types, some of which are listed below. +@defvr {Scheme Variable} system-service-type +This is the root of the service graph. It produces the system directory +as returned by the @command{guix system build} command. +@end defvr + @defvr {Scheme Variable} boot-service-type -The type of the ``boot service'', which is the root of the service -graph. +The type of the ``boot service'', which produces the @dfn{boot script}. +The boot script is what the initial RAM disk runs when booting. @end defvr @defvr {Scheme Variable} etc-service-type diff --git a/doc/images/service-graph.dot b/doc/images/service-graph.dot index 3397b878e9..04f231bb09 100644 --- a/doc/images/service-graph.dot +++ b/doc/images/service-graph.dot @@ -4,7 +4,8 @@ digraph "Service Type Dependencies" { etc [shape = box, fontname = Helvetica]; accounts [shape = box, fontname = Helvetica]; activation [shape = box, fontname = Helvetica]; - boot [shape = house, fontname = Helvetica]; + boot [shape = box, fontname = Helvetica]; + system [shape = house, fontname = Helvetica]; lshd -> dmd; lshd -> pam; udev -> dmd; @@ -32,4 +33,6 @@ digraph "Service Type Dependencies" { guix -> dmd; guix -> activation; guix -> accounts; + boot -> system; + etc -> system; } |