Useful tricks

Useful tricks in Linux using and server managing
(specifically, a Ubuntu desktop version and a server version)

1. Use ls -lh to identify the size of your files
2. To mount your portable disk on a Ubuntu PC, you need to sudo mkdir /mnt/my_disk1 and then sudo mount /dev/sdf1 /mnt/my_disk1/. After these steps, you will be able to read and operate your disk via /mnt/my_disk1
3. To unmount your disk, just try sudo umount /dev/sdf1 and then pull off your disk.
4. Record the file structure of 4 level in current directory. sudo tree -L 4 | sudo tee log.txt
5. The advance media player is mplayer
6. Use rename to rename all the files under a folder rename 's/(..)(.*)/$2/p' *.txt
7. Use dos2unix to erease the windows style ^M at the end of each line.
8. Delete the \n of all the lines in a file / Merge all the lines into one single line awk '{printf $0}' 1.txt
9. Mount a NTFS disk of hypenating windows in Ubuntu

        sudo mkdir /media/windows /media/D
        sudo mount -t ntfs-3g -o ro /dev/sda4 /media/windows
        sudo mount -t ntfs-3g -o ro /dev/sda6 /media/D

OR

sudo  ntfsfix /dev/sdXY

where XY is the partition, e.g. a2 (/dev/sda2)

2. Check the dependency of a software, take octave as an example sudo apt-get build-dep octave

3. Shutdown the Bluetooth function from the beginning. Add this sentence to rc.local rfkill block bluetooth

4. Solve the problem of Permission denied: "/home/XXX/.gvfs"

umount /home/$USER/.gvfs
rm -rf .gvfs/

13. Check memory info in Ubuntu

sudo dmidecode -t memory

14 Change the character coding for file name
First things first, install convmv

sudo apt-get install convmv

• circumstance 1
  Change all document into utf8

convmv -f gbk -t utf8 --notest *

• circumstance 2
  If above method fails, it may be cause by some idots claiming the code to be GBK but actually windows-1252

convmv -f utf8 -t windows-1252 --notest *
convmv -f gbk -t utf8 --notest *

使用技巧

中文版？不存在的，脑子一热就写了英文的