pacman -Qqe | fzf --preview 'pacman -Qiil {}' --layout=reverse --bind 'enter:execute(pacman -Qiil {} | less)'copy

pacman -Slq | fzf --preview 'pacman -Si {}' --layout=reversecopy

pacman -D --asdeps $(pacman -Qqe)copy

pacman -D --asexplicit base linux linux-firmwarecopy

cat explicit | sudo pacman -D --asexplicit -copy

pacman -Qii | awk '/^MODIFIED/ {print $2}'copy

pacman -Qi | awk '/^Name/{name=$3} /^Install Date/{print $4,$5,$6,name}' | sortcopy

SYNOPSIS
       Usage: expac [options] <format> targets...

OPTIONS
       -Q, --query
           Search  the local database for provided targets. This is the default
           behavior.

       -S, --sync
           Search the sync databases for provided targets.

       -s, --search
           Search for packages matching the strings specified by targets.  This
           is a boolean AND query and regex is allowed.

       -g, --group
           Return packages matching the specified targets as package groups.

       --config <file>
           Read from file for alpm initialization instead of /etc/pacman.conf.

       -H, --humansize <size>
           Format  package  sizes  in SI units according to size. Valid options
           are:

             B, K, M, G, T, P, E, Z, Y

       -1, --readone
           Stop searching after the first result. This only has an effect on -S
           operations without -s.

       -d, --delim <string>
           Separate each package with the specified string. The  default  value
           is a newline character.

       -l, --listdelim <string>
           Separate  each  list  item  with the specified string. Lists are any
           interpreted sequence specified with a capital  letter.  The  default
           value is two spaces.

       -p, --file
           Interpret targets as paths to local files.

       -t, --timefmt <format>
           Output time described by the specified format. This string is passed
           directly to strftime(3). The default format is %c.

       -v, --verbose
           Output  more.  ‘Package  not  found' errors will be shown, and empty
           field values will display as 'None'.

       -V, --version
           Display version information and quit.

       -h, --help
           Display the help message and quit.

FORMATTING
       The format argument allows the following interpreted sequences:

         %a    architecture

         %B    backup files

         %b    build date

         %C    conflicts with (no version strings)

         %D    depends on

         %d    description

         %E    depends on (no version strings)

         %e    package base

         %f    filename (only with -S)

         %F    files (only with -Q)

         %g    base64 encoded PGP signature (only with -S)

         %G    groups

         %H    conflicts with

         %h    sha256sum

         %i    has install scriptlet (only with -Q)

         %k    download size (only with -S)

         %l    install date (only with -Q)

         %L    licenses

         %m    install size

         %M    modified backup files (only with -Q)

         %n    package name

         %N    required by

         %O    optional deps

         %o    optional deps (no descriptions)

         %p    packager name

         %P    provides

         %R    replaces (no version strings)

         %r    repo

         %s    md5sum

         %S    provides (no version strings)

         %T    replaces

         %u    project URL

         %V    package validation method

         %v    version

         %w    install reason (only with -Q)

         %!    result number (auto-incremented counter, starts at 0)

         %%    literal %

       Note that for any lowercase tokens aside from %m  and  %k,  full  printf
       support  is  allowed, e.g. %-20n. This does not apply to any list based,
       date, or numerical output.

       Standard backslash escape sequences are supported, as per printf(1).

EXAMPLES
       Emulate pacman's search function:

         $ expac -Ss '%r/%n %v\n    %d' <search terms>

       List the oldest 10 installed packages (by build date):

         $ expac --timefmt=%s '%b\t%n' | sort -n | head -10copy

  List the dependencies of a package:

      expac [-S|--sync] '%D' package

  List the optional dependencies of a package:

      expac [-S|--sync] "%o" package

  List the download size of packages in MiB:

      expac [-S|--sync] [-H|--humansize] M '%k\t%n' package1 package2 ...

  List packages marked for upgrade with their download size:

      expac [-S|--sync] [-H|--humansize] M '%k\t%n' $(pacman -Qqu) | sort [-sh|--sort --human-numeric-sort]

  List explicitly-installed packages with their optional dependencies:

      expac [-d|--delim] '\n\n' [-l|listdelim] '\n\t' [-Q|--query] '%n\n\t%O' $(pacman -Qeq)copy

expac -Q "%n %w %M" | grep explicit | awk '{print $3}' | grep -v ^$copy

groups=('modified')copy

IgnoreGroup = modifiedcopy

npm -g install pake-clicopy

pake chat.deepseek.com --name deepseek --width 1080 --height 1920 --show-system-tray --icon 512x512-RGBA.pngcopy

control.tar.gz
data.tar.gz
debian-binarycopy

 usr
├──  bin
│   └──  pake
├──  lib
│   └──  deepseek
│       └──  png
│           └──  deepseek_512.png
└──  share
    ├──  applications
    │   └──  deepseek.desktop
    └──  icons
        └──  hicolor
            └──  512x512
                └──  apps
                    └──  pake.pngcopy

# Maintainer: hiraethecho <wyz2016zxc at outlook dot com>
pkgname="${_appname}-pake"
pkgver=1.0.0
pkgrel=1
pkgdesc="${_appname} pake"
arch=('x86_64')
license=('MIT')
conflicts=("${_appname}-pake")
depends=(
    'gtk3'
    'webkit2gtk-4.1'
)
source=(
  ${_appname}.deb
)
sha256sums=('SKIP')
prepare() {
    bsdtar -xf "${srcdir}/data."*
    sed -e "
        s/Exec=pake/Exec=${_appname}/g
        s|Icon=pake|Icon=${_appname}|g
    " -i "${srcdir}/usr/share/applications/${_appname}.desktop"
    mv ${srcdir}/usr/share/icons/hicolor/*/apps/pake.png ${srcdir}/usr/share/icons/pake.png
}
package() {
    install -Dm755 "${srcdir}/usr/bin/pake" "${pkgdir}/usr/bin/${_appname}"
    install -Dm644 "${srcdir}/usr/share/applications/${_appname}.desktop" "${pkgdir}/usr/share/applications/${_appname}.desktop"
    install -Dm644 "${srcdir}/usr/share/icons/pake.png" "${pkgdir}/usr/share/pixmaps/${_appname}.png"
}copy

#!/usr/bin/bash
# generate a zst from pake
url=""
icon=""
name=""
while getopts ":n:i:w:" opt; do
  case $opt in
  n) name="$OPTARG" ;;
  i) icon="$OPTARG" ;;
  w) url="$OPTARG" ;;
  \?)
    echo "无效选项: -$OPTARG" >&2
    ;;
  esac
done

echo -e "$url $icon $name"
# pake $url --icon $icon --height=1080 --width=1920 --show-system-tray --name $appname
sed -i "/pkgdesc/a\\url=${url}" PKGBUILD
sed -i "/pkgname/i\\_appname=${name}" PKGBUILD
makepkgcopy

fc-list -f '%{file}\n' :lang=zhcopy

fc-match monospacecopy

<?xml version="1.0"?>
<!DOCTYPE fontconfig SYSTEM "fonts.dtd">
<fontconfig>
<alias>
   <family>serif</family>
   <prefer>
     <family>LXGW Wenkai mono</family>
   </prefer>
 </alias>
<alias>
   <family>monospace</family>
   <prefer>
     <family>CodeNewRoman Nerd Font</family>
     <family>LXGW Wenkai mono</family>
   </prefer>
 </alias>
</fontconfig>copy

useradd -m USERNAME
passwd USERNAMEcopy

useradd -m --btrfs-subvolume-home USERNAMEcopy

usermod -aG wheel USERNAMEcopy

useradd -m -G wheel USERNAMEcopy

EDITOR=nvim visudocopy

# %wheel ALL=(ALL:ALL)copy

# /etc/pacman.d/mirrorlist
Server = https://mirrors.tuna.tsinghua.edu.cn/archlinux/$repo/os/$archcopy

[archlinuxcn]
Server = https://mirrors.tuna.tsinghua.edu.cn/archlinuxcn/$archcopy

pacman -Sy archlinux-keyring
pacman -Sy archlinuxcn-keyringcopy

pacman -Syyucopy

pacman -S parucopy

paccache -r # 清理缓存,仅包含最近的三个版本
paccache -rk1 # 清理缓存,仅包含最近的1个版本
pacman -Sc # 清理未安装软件包
pacman -Scc # 清理缓存中所有内容
sudo pacman -Rcsn $(pacman -Qdtq -)
journalctl --vacuum-size=50M #限制日志copy

# /etc/iwd/main.conf
[General]
EnableNetworkConfiguration=truecopy

systemctl enable dhcpcdcopy

[device]
wifi.backend=iwdcopy

systemctl mask wpa_supplicant
systemctl enable iwdcopy

sudo pacman -S alsa-ultis pulseaudio pavucontrol
pulseaudio --check
pulseaudio -Dcopy

sudo pacman -S acpilight
sudo gpasswd video -a _username_ # 或者
sudo usermod -aG video _username_copy

sudo systemctl enable bluetooth.service --nowcopy

xinput list | grep -i "Touchpad" | awk '{print $6}' | sed 's/[^0-9]//g'copy

setxkbmap -option ctrl:nocaps &
xcape -e 'Control_L=Return' &
xcape -e 'Alt_L=Escape' &copy

upower -e

/org/freedesktop/UPower/devices/line_power_ACAD
/org/freedesktop/UPower/devices/battery_BAT1
/org/freedesktop/UPower/devices/DisplayDevicecopy

sudo pacman -S mesa lib32-mesa xf86-video-amdgpu vulkan-radeon lib32-vulkan-radeoncopy

id -u
id -gcopy

sudo mkdir /media/gamediskcopy

# /etc/fstab
UUID=38CE9483CE943AD8 /media/gamedisk lowntfs-3g uid=1000,gid=1000,rw,user,exec,umask=000 0 0copy

mkdir -p ~/.steam/steam/steamapps/compatdata
ln -s ~/.steam/steam/steamapps/compatdata /media/gamedisk/Steam/steamapps/copy

[Desktop Entry]
Name=wechat
Name[zh_CN]=微信
Exec=env XMODIFIERS="@im=fcitx" GTK_IM_MODULE="fcitx" QT_IM_MODULE="fcitx" /usr/bin/wechat %U
StartupNotify=true
Terminal=false
Icon=/opt/wechat/icons/wechat.png
Type=Application
Categories=Utility;
Comment=Wechat Desktop
Comment[zh_CN]=微信桌面版copy

typedef struct {
    int i;
    float f;
} Arg1;copy

typedef union {
    int i;
    float f;
    void *v;
} Arg2;copy

_NET_WM_ICON_NAME(UTF8_STRING) = "~"
WM_ICON_NAME(UTF8_STRING) = "~"
WM_CLASS(STRING) = "name", "class"
_NET_WM_NAME(UTF8_STRING) = "~"
WM_NAME(UTF8_STRING) = "~"copy

WM_NAME(UTF8_STRING) = "~"
_NET_WM_NAME(UTF8_STRING) = "~"
WM_CLASS(STRING) = "scratchpad", "tabbed"copy

  selmon->tagset[selmon->seltags] &= ~scratchtag;
  if (!strcmp(c->name, scratchpadname)) {
    c->mon->tagset[c->mon->seltags] |= c->tags = scratchtag;
    c->isfloating = True;
  }copy

void manage(Window w, XWindowAttributes *wa) {
  Client *c, *t = NULL;
+ XClassHint ch = {NULL, NULL};
+ const char *class, *instance;
    ...
+ XGetClassHint(dpy, c->win, &ch);
+  instance = ch.res_name ? ch.res_name : broken;
  selmon->tagset[selmon->seltags] &= ~scratchtag;
~ if (!strcmp(instance, scratchpadname)) {
    c->mon->tagset[c->mon->seltags] |= c->tags = scratchtag;
    c->isfloating = True;
  }
}copy

  XGetClassHint(dpy, c->win, &ch);
  class = ch.res_class ? ch.res_class : broken;
  instance = ch.res_name ? ch.res_name : broken;

  for (i = 0; i < LENGTH(rules); i++) {
    r = &rules[i];
    if ((!r->title || strstr(c->name, r->title)) &&
        (!r->class || strstr(class, r->class)) &&
        (!r->instance || strstr(instance, r->instance))) {
      c->isfloating = r->isfloating;
      c->tags |= r->tags;
      c->opacity = r->opacity;
      c->unfocusopacity = r->unfocusopacity;
      for (m = mons; m && m->num != r->monitor; m = m->next) ;
      if (m)
        c->mon = m;
    }
  }copy

iwctl # 进入iwctl
[iwd] help # 查看使用方法
[iwd] station wlan0 connect **SSID** # example
[iwd] exit # 退出iwctlcopy

timedatectl set-ntp true
timedatectl statuscopy

Server = https://mirrors.tuna.tsinghua.edu.cn/archlinux/$repo/os/$archcopy

fdisk -lcopy

mkfs.btrfs  -L btrfs-arch /dev/nvme0n1p5 # -L means label, can be omittedcopy

mount -o /dev/nvme0n1p3 /mnt # 这条命令将分区挂载到btrfs的顶级子卷，即 / 子卷， id=5
# 通常这些子卷
btrfs subvolume create /mnt/@   # 创建顶级子卷下的 @ 子卷，将作为新linux的 / 目录
btrfs subvolume create /mnt/@home # 创建顶级子卷下的 /@home 子卷，将作为新linux的 用户家目录，即 /home
# 以下可选
btrfs subvolume create /mnt/@log
btrfs subvolume create /mnt/@cache
btrfs subvolume create /mnt/@opt
btrfs subvolume create /mnt/@tmp
btrfs subvolume create /mnt/@rootcopy

btrfs subvolume list /mnt
ID 256 gen 405 parent 5 top level 5 path @
ID 257 gen 409 parent 5 top level 5 path @homecopy

umount /mnt

mount -o noatime,nodiratime,compress=zstd,subvol=@ /dev/nvme0n1p5 /mnt #挂载 @ 子卷到新系统的 / 目录
mkdir -p /mnt/{boot/efi,home,var/{log,cache}} #创建新系统的 /boot/efi、/home、/var/log、/var/cache
mount -o noatime,nodiratime,compress=zstd,subvol=@home -m /dev/nvme0n1p5 /mnt/home # -m 创建挂载的文件夹
# 如果创建了对应子卷，那么
mount -o noatime,nodiratime,compress=zstd,subvol=@log -m /dev/nvme0n1p5 /mnt/var/log
mount -o noatime,nodiratime,compress=zstd,subvol=@cache -m /dev/nvme0n1p5 /mnt/var/cache
mount -o noatime,nodiratime,compress=zstd,subvol=@tmp -m /dev/nvme0n1p5 /mnt/tmp
mount -o noatime,nodiratime,compress=zstd,subvol=@opt -m /dev/nvme0n1p5 /mnt/opt
mount -o noatime,nodiratime,compress=zstd,subvol=@root -m /dev/nvme0n1p5 /mnt/rootcopy

findmnt -nt btrfscopy

mount /dev/nvme0n1p1 /mnt/boot/eficopy

mkdir -p /mnt/efi
mount /dev/nvme0n1p1 /mnt/boot/eficopy

chattr +C /mnt/tmp
chattr +C /mnt/var/cache
chattr +C /mnt/var/logcopy

pacstrap -K -M /mnt base base-devel linux linux-headers btrfs-progs iwd neovim git
sudo grub os-prober efibootmgr amd-ucode dhcpcdcopy

genfstab -U /mnt >> /mnt/etc/fstabcopy

arch-chroot /mntcopy

grub-install --target=x86_64-efi --efi-directory=/boot/efi --bootloader-id=arch --recheckcopy

grub-mkconfig -o /boot/grub/grub.cfgcopy

passwd rootcopy

ln -sf /usr/share/zoneinfo/Region/City /etc/localtime #替换Region/City为你所在区域，例如Asia/Shanghai
hwclock --systohc # 同步硬件时钟
timedatectl set-ntp true
timedatectl set-local-rtc true #同步双系统时间
echo "en_US.UTF-8 UTF-8" >> /etc/locale.gen
locale-gen
echo "LANG=en_US.UTF-8" > /etc/locale.conf #或者编辑文件，取消注释
systemctl enable NetworkManager.service # 启动网络服务
hostnamectl set-hostname <yourhostname> # 设置主机名copy

echo "LC_TIME=C.UTF-8" >> /etc/locale.conf # >> 表示追加。copy

# /etc/hosts
127.0.0.1   localhost
::1         localhost
127.0.1.1   <yourhostname>.localdomain    <yourhostname>copy

exit #退出chroot
umount /mnt/boot/efi
umount /mnt/home
umount /mnt
rebootcopy

BTRFS(8)                             BTRFS                             BTRFS(8)

NAME
       btrfs - a toolbox to manage btrfs filesystems

SYNOPSIS
       btrfs [global options] <group> [<group>...] <command> [options] [<args>]

DESCRIPTION
       The  btrfs  utility  is a toolbox for managing btrfs filesystems.  There
       are command groups to work with subvolumes, devices, for whole  filesys‐
       tem or other specific actions. See section COMMANDS.

       There  are also standalone tools for some tasks like btrfs-convert(8) or
       btrfstune(8) that were separate historically and/or haven't been  merged
       to the main utility. See section STANDALONE TOOLS for more details.

       For  other topics (mount options, etc) please refer to the separate man‐
       ual page btrfs(5).

COMMAND SYNTAX
       Any command name can be shortened so long as the shortened form is unam‐
       biguous, however, it  is  recommended  to  use  full  command  names  in
       scripts.  All command groups have their manual page named btrfs-<group>.

       For example: it is possible to run btrfs sub snaps instead of btrfs sub‐
       volume snapshot.  But btrfs file s is not allowed, because file s may be
       interpreted both as filesystem show and as filesystem sync.

       If  the  command  name  is ambiguous, the list of conflicting options is
       printed.

       Sizes, both upon input and output, can be  expressed  in  either  SI  or
       IEC-I  units  (see  numfmt(1))  with the suffix B appended.  All numbers
       will be formatted according to the rules of the C locale  (ignoring  the
       shell locale, see locale(7)).

       For  an  overview  of  a given command use btrfs command --help or btrfs
       [command...] help --full to print all available  options  for  all  com‐
       mands.

       There  are  global  options  that are passed between btrfs and the group
       name and affect behaviour not specific to the command, e.g. verbosity or
       the type of the output:

          btrfs -q subvolume create ...
          btrfs --dry-run subvolume create ...

       --format <format>
              if supported by the command, print subcommand output in that for‐
              mat (text, json)

       -v|--verbose
              increase verbosity of the subcommand

       -q|--quiet
              print only errors

       --log <level>
              set log level (default, info, verbose, debug, quiet)

       The remaining options are relevant only for the main tool:

       --help print condensed help for all subcommands

       --version
              print version string

COMMANDS
       balance
              Balance btrfs filesystem chunks across single or several devices.
              See btrfs-balance(8) for details.

       check  Do off-line check on a btrfs filesystem.  See btrfs-check(8)  for
              details.

       device Manage devices managed by btrfs, including add/delete/scan and so
              on.  See btrfs-device(8) for details.

       filesystem
              Manage  a  btrfs  filesystem, including label setting/sync and so
              on.  See btrfs-filesystem(8) for details.

       inspect-internal
              Debug       tools       for       developers/hackers.         See
              btrfs-inspect-internal(8) for details.

       property
              Get/set a property from/to a btrfs object.  See btrfs-property(8)
              for details.

       qgroup Manage   quota   group(qgroup)   for   btrfs   filesystem.    See
              btrfs-qgroup(8) for details.

       quota  Manage quota on btrfs filesystem like  enabling/rescan  and  etc.
              See btrfs-quota(8) and btrfs-qgroup(8) for details.

       receive
              Receive  subvolume data from stdin/file for restore and etc.  See
              btrfs-receive(8) for details.

       replace
              Replace btrfs devices.  See btrfs-replace(8) for details.

       rescue Try to rescue damaged btrfs filesystem.  See btrfs-rescue(8)  for
              details.

       restore
              Try  to  restore  files  from  a  damaged  btrfs filesystem.  See
              btrfs-restore(8) for details.

       scrub  Scrub a btrfs filesystem.  See btrfs-scrub(8) for details.

       send   Send subvolume data to  stdout/file  for  backup  and  etc.   See
              btrfs-send(8) for details.

       subvolume
              Create/delete/list/manage       btrfs       subvolume.        See
              btrfs-subvolume(8) for details.

STANDALONE TOOLS
       New functionality could be provided using  a  standalone  tool.  If  the
       functionality  proves to be useful, then the standalone tool is declared
       obsolete and its functionality is copied  to  the  main  tool.  Obsolete
       tools are removed after a long (years) depreciation period.

       Tools that are still in active use without an equivalent in btrfs:

       btrfs-convert
              in-place conversion from ext2/3/4 filesystems to btrfs

       btrfstune
              tweak some filesystem properties on a unmounted filesystem

       btrfs-select-super
              rescue tool to overwrite primary superblock from a spare copy

       btrfs-find-root
              rescue helper to find tree roots in a filesystem

       For  space-constrained environments, it's possible to build a single bi‐
       nary with functionality of several standalone tools. This  is  following
       the  concept  of  busybox where the file name selects the functionality.
       This works for symlinks or hardlinks. The full list can be  obtained  by
       btrfs help --box.

EXIT STATUS
       btrfs returns a zero exit status if it succeeds. Non zero is returned in
       case of failure.

AVAILABILITY
       btrfs  is  part  of btrfs-progs.  Please refer to the documentation at ‐
       https://btrfs.readthedocs.io.

SEE ALSO
       btrfs(5),    btrfs-balance(8),     btrfs-check(8),     btrfs-convert(8),
       btrfs-device(8),     btrfs-filesystem(8),     btrfs-inspect-internal(8),
       btrfs-property(8),  btrfs-qgroup(8),  btrfs-quota(8),  btrfs-receive(8),
       btrfs-replace(8),   btrfs-rescue(8),  btrfs-restore(8),  btrfs-scrub(8),
       btrfs-send(8), btrfs-subvolume(8), btrfstune(8), mkfs.btrfs(8)

6.14                              Mar 27, 2025                         BTRFS(8)copy

ID 257 gen 96108 top level 5 path @home
ID 318 gen 105959 top level 257 path @home/username
ID 268 gen 96108 top level 318 path @home/username/.snapshots
ID 269 gen 96108 top level 268 path @home/username/.snapshots/1/snapshot
ID 258 gen 105883 top level 5 path @root
ID 259 gen 105850 top level 5 path @cache
ID 260 gen 105959 top level 5 path @log
ID 261 gen 105942 top level 5 path @tmp
ID 262 gen 98722 top level 5 path @opt
ID 273 gen 96108 top level 262 path @opt/.snapshots
ID 274 gen 96108 top level 258 path @root/.snapshots
ID 285 gen 96433 top level 274 path @root/.snapshots/1/snapshot
ID 290 gen 105959 top level 5 path @
ID 519 gen 96445 top level 268 path @home/username/.snapshots/2/snapshot
ID 536 gen 103272 top level 5 path timeshift-btrfs/snapshots/2025-04-21_12-54-20/@
ID 537 gen 104133 top level 5 path timeshift-btrfs/snapshots/2025-04-21_20-12-43/@copy

ID 257 gen 96108 top level 5 path @home
ID 258 gen 105883 top level 5 path @root
ID 259 gen 105850 top level 5 path @cache
ID 260 gen 105930 top level 5 path @log
ID 261 gen 105928 top level 5 path @tmp
ID 262 gen 98722 top level 5 path @opt
ID 290 gen 105929 top level 5 path @copy

sudo snapper -c [name of config] create-config [path-to-subvol]copy

sudo snapper -c root create-config /copy

sudo umount /.snapshots
sudo rm -r /.snapshots
sudo btrfs subvolume delete /.snapshots
sudo mkdir /.snapshots
sudo mount -o subvol=/ /dev/nvme0n1p1 /mnt
sudo btrfs subvolume create /mnt/@snapshotscopy

useradd

Usage: useradd [options] LOGIN
       useradd -D
       useradd -D [options]
Options:
      --btrfs-subvolume-home    use BTRFS subvolume for home directorycopy

sudo mount /dev/nvme0n1p6 /mnt
cd /mnt
sudo mv /mnt/@ /mnt/@.broken
sudo btrfs subvolume snapshot /mnt/@snapshots/{number}/snapshot /mnt/@
sudo btrfs subvolume delete /mnt/@.brokencopy

sudo mount -o subvol=/ /dev/nvme0n1p1 /mnt
sudo btrfs subvolume snapshot /mnt/@ /mnt/@bad
sudo btrfs subvolume delete /mnt/@
sudo btrfs subvolume snapshot /mnt/@snapshots/要恢复的快照号/snapshot /mnt/@copy

#!/bin/sh
set -e
if [[ x"$1" == x ]]; then
  echo "No snapshot number given." 1>&2
  echo "Usage: rollback [snapshot to rollback]" 1>&2
  exit 1
fi
root_dev=`findmnt -n -o SOURCE / | sed 's/\[.*\]//g'`
root_subvol=`findmnt -n -o SOURCE / | sed 's/.*\[\(.*\)\].*/\1/'`
echo ">= Rollback to #$1 on device $root_dev"
# create snapshot before
sudo snapper create --read-only --type single -d "Before rollback to #$1" --userdata important=yes
sudo mount -o subvol=/ $root_dev /mnt
# check enviornment
if [[ x"$root_subvol" == x/@ ]]; then
  echo "Warning: Not run in a snapshot, a subvolume @old will be created. You should consider remove it after reboot." 1>&2
  if [[ -d /mnt/@old ]]; then
    echo "Found last @old, remove it."
    sudo btrfs subvolume delete /mnt/@old >/dev/null
  fi
  sudo mv /mnt/@ /mnt/@old
else
  sudo btrfs subvolume delete /mnt/@ >/dev/null
fi
sudo btrfs subvolume snapshot /mnt/@snapshots/$1/snapshot /mnt/@ >/dev/null
sudo umount /mntcopy

snapper -c [config] rollback [number]copy

btrfs filesystem du -s /path/to/subvolumecopy