guix system: Add "--file-system-type" option.

* guix/scripts/system.scm (process-action): Pass file-system-type to ...
(perform-action): ... here.  Add new keyword argument.  Pass new value to ...
(system-derivation-for-action): ... here.  Add new keyword argument.
Pass new value to system-disk-image.
* doc/guix.texi (disk-image): Document new option.

1 files changed, 16 insertions, 0 deletions

diff --git a/doc/guix.texi b/doc/guix.texi
index d61a5b7514..811031697c 100644
--- a/doc/guix.texi
+++ b/doc/guix.texi
@@ -16190,6 +16190,9 @@ in @var{file} that stands alone.  By default, @command{guix system}
 estimates the size of the image needed to store the system, but you can
 use the @option{--image-size} option to specify a value.
 
+You can specify the root file system type by using the
+@option{--file-system-type} option.  It defaults to "ext4".
+
 When using @code{vm-image}, the returned image is in qcow2 format, which
 the QEMU emulator can efficiently use. @xref{Running GuixSD in a VM},
 for more information on how to run the image in a virtual machine.
@@ -16245,6 +16248,19 @@ This works as per @command{guix build} (@pxref{Invoking guix build}).
 Return the derivation file name of the given operating system without
 building anything.
 
+@item --file-system-type=@var{type}
+@itemx -t @var{type}
+For the @code{disk-image} action, create a file system of the given
+@var{type} on the image.
+
+When this option is omitted, @command{guix system} uses @code{ext4}.
+
+@cindex ISO-9660 format
+@cindex CD image format
+@cindex DVD image format
+@code{--file-system-type=iso9660} produces an ISO-9660 image, suitable
+for burning on CDs and DVDs.
+
 @item --image-size=@var{size}
 For the @code{vm-image} and @code{disk-image} actions, create an image
 of the given @var{size}.  @var{size} may be a number of bytes, or it may