From cfa6fdc54c58280e49330438aecfb5046ee9e63a Mon Sep 17 00:00:00 2001 From: Josselin Poiret Date: Sun, 6 Feb 2022 22:20:45 +0100 Subject: doc: Clarify the Swap Space examples, and include an helper example. MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit * doc/guix.texi (Swap Space): The examples referred to variables defined outside of the snippets, and so were not very informative for people without much Guile knowledge. Instead, refer to mapped-devices for the first, and use the new helper file-systme-mount-point-predicate for the second. Signed-off-by: Ludovic Courtès --- doc/guix.texi | 33 +++++++++++++++++++++++++-------- 1 file changed, 25 insertions(+), 8 deletions(-) (limited to 'doc') diff --git a/doc/guix.texi b/doc/guix.texi index a05f073c3d..039b418038 100644 --- a/doc/guix.texi +++ b/doc/guix.texi @@ -15742,22 +15742,39 @@ Linux swap partition by running @command{swaplabel @var{device}}, where @lisp (swap-space (target (file-system-label "swap")) - (dependencies (list lvm-device))) + (dependencies mapped-devices)) @end lisp -Use the partition with label @code{swap}, which can be found after the -@var{lvm-device} mapped device has been opened. Again, the +Use the partition with label @code{swap}, which can be found after all +the @var{mapped-devices} mapped devices have been opened. Again, the @command{swaplabel} command allows you to view and change the label of a Linux swap partition. +Here's a more involved example with the corresponding @code{file-systems} part +of an @code{operating-system} declaration. + @lisp -(swap-space - (target "/btrfs/swapfile") - (dependencies (list btrfs-fs))) +(file-systems + (list (file-system + (device (file-system-label "root")) + (mount-point "/") + (type "ext4")) + (file-system + (device (file-system-label "btrfs")) + (mount-point "/btrfs") + (type "btrfs")))) + +(swap-devices + (list + (swap-space + (target "/btrfs/swapfile") + (dependencies (filter (file-system-mount-point-predicate "/btrfs") + file-systems))))) @end lisp -Use the file @file{/btrfs/swapfile} as swap space, which is present on the -@var{btrfs-fs} filesystem. +Use the file @file{/btrfs/swapfile} as swap space, which depends on the +file system mounted at @file{/btrfs}. Note how we use Guile's filter to +select the file system in an elegant fashion! @node User Accounts @section User Accounts -- cgit v1.2.3