Add readme.

README.md

@@ -0,0 +1,20 @@
+# tarback
+
+Create a tar archive from remote resources.
+
+This is more or less equivalent to `ssh host tar files | xz | split
+output-file` and its reverse.
+
+Two plugins are available:
+- `ssh` handles all the ssh command and filename escaping necessary
+- `docker` instead of backing up a remote volume, back up a docker volume
+
+## usage
+
+`tarback -p ssh,docker -s 'ssh $user@$host' create "$remote_volume_name" "$local_tar_archive"`
+
+Create a split tar archive of the remote volume, with the extensions `part{a-z,a-z}`.
+
+`tarback -p ssh,docker -s 'ssh $user@$host' restore "$local_tar_archive" "$remote_volume_name"`
+
+Restore the backup to the remote docker volume.

tarback/docker.sh

@@ -3,3 +3,7 @@
 _tarback_plugin_docker_cmd='docker run -i --rm --workdir=/mnt --volume="$1":/mnt/"$1" alpine '
 TARBACK_TAR_CREATE_COMMAND="$_tarback_plugin_docker_cmd "'tar c -C "/mnt/$1" .'
 TARBACK_TAR_EXTRACT_COMMAND="$_tarback_plugin_docker_cmd "'tar x -C "/mnt/$1"'
+
+# Can set file to same as directory command since a docker volume is always a directory
+TARBACK_TAR_CREATE_COMMAND_FILE="$_tarback_plugin_docker_cmd "'tar c -C "/mnt/$1" .'
+TARBACK_TAR_EXTRACT_COMMAND_FILE="$_tarback_plugin_docker_cmd "'tar x -C "/mnt/$1"'