archbuild: add doc for bind mount config

Signed-off-by: Celeste Liu <CoelacanthusHex@gmail.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/doc/man/archbuild.1.asciidoc b/doc/man/archbuild.1.asciidoc
index 6b00572..777e3f2 100644
--- a/doc/man/archbuild.1.asciidoc
+++ b/doc/man/archbuild.1.asciidoc
@@ -25,6 +25,7 @@ Description
 
 The symlink used to run it will be inspected by archbuild, to determine which target you want it to use. It will load the available pacman configuration from 'pacman-reponame-arch.conf' with a fallback to 'pacman-reponame.conf' from {pkgdatadir}. The makepkg configuration is loaded from 'makepkg-repo-arch.conf' with a fallback to 'makepkg-reponame.conf' from {pkgdatadir}.
 
+It will also load the bind mount configuration from 'mount.d/arch' in {pkgdatadir}. The file format is that each line starting with ro and rw will be used, other lines will be ignored, and the rest of the used line is out/path:in/path preceded by a space as a separator. ro means it is a read-only mount, rw means a read-write mount.
 
 Options
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