Shell Tricks
Hotkeys (bash)
Alt + . Esc, . | Add last argument of most recent command. |
Ctrl + A Ctrl + E | Jump to start or end of the line. |
Ctrl + D | Disconnect / exit current shell |
Snippets
do something with multiple files
You can use find and the -exec
option.
For example if you want to extract multiple .rar files:
find . -name '*.rar' -exec 'unrar' 'e' '{}' \;
{}
gets replaced with the filename found by find . -name '*.rar'
. Watch out that you have to single-quote ('
) every option to the program you're -exec
uting.
open multiple files in image viewer
for file in *.jpg; do feh $file&; done
The &
makes it run in the background and opens all files at once.
urlencode text
echo "text" | jq -sRr @uri
(source)
compare md5sum with given string
md5sum -c - <<<"b4460802b5853b7bb257fbf071ee4ae2 file_name.ext"
generate 4 letter password
shuf -n 4 /usr/share/dict/ngerman
mount partition from dd image
losetup --partscan --find --show sd.img lsblk | grep loop mount /dev/loop0p2 sd/
ssh without executing .login
ssh -t user@host /bin/bash
generate crypt(3) output for /etc/shadow
mkpasswd # on debian openssl passwd -crypt myPassword
convert ext2/ext3 to ext4
tune2fs -O extents,uninit_bg,dir_index,has_journal /dev/sdx0
backup MBR (Master Boot Record)
# Use 446 bytes to overwrite or restore your /dev/XYZ MBR boot code only with the contents of $mbr.backup.file. # Use 512 bytes to overwrite or restore your /dev/XYZ the full MBR (which contains both boot code and the drive’s partition table) with the contents of $mbr.backup.file. dd if=/dev/sdx of=mbr.img bs=512 count=1
check & wipe drive
badblocks -t random -wsv /dev/disk/by-id/drive-id
compare the contents of two folders
diff -rq dir1 dir2
login with empty password
passwd -d USERNAME usermod -U USERNAME
disable gnome-keyring in favor of ssh-agent
chmod 0 /usr/bin/gnome-keyring-daemon
hide process informations from other users
mount -o remount,rw,hidepid=2 /proc
save current X.org config
sudo X :2 -configure
find out current Kernel boot options
cat /proc/cmdline
similar sites
- commandlinefu.com – It's like Kung Fu, but for the command line. User contributed useful snippets.