Teodor Muraru

Usability settings:

• move window-bar action buttons from left (Ubuntu 10.10/Mac) to right:

  gconftool-2 – type string – set /apps/metacity/general/button_layout "menu:minimize,maximize,close"

• remove confirmation for logout: System Settings -> Advanced -> Session Manager -> Confirm Logout
• remove screen-lock after screensaver: Control Center -> Screensaver -> Lock screen when screensaver is active (uncheck)

Processes management:

• move a process to background (suspend):

  CTRL-z

• list background/suspended processes:

  jobs (returns a list of ids of the stopped processes and their description: [1]+  Stopped  mc)

• bring process to foreground:

  fg 1 (where 1 is the id of the desired process to resurrect from the above list)

Computer info:

Inventory:

• # lists your hardware

  $ sudo lshw

• # lists all hard disk

  $ sudo lshw -C disk

• # xports an html page with hardware details

  $ sudo lshw -html > your-file-name.html

Sensors monitoring:

• sudo apt-get install lm-sensors sensors-applet  #(ksensors for Kubuntu)

• sudo sensors-detect

To see if your running kernel is 32-bit or 64-bit, just issue the following command:

• $ uname -m
  x86_64 indicates a running 64-bit kernel. If you use see i386, i486, i586 or i686, you're running a 32-bit kernel. Note: x86_64 is synonymous with amd64.

How to find out the Ubuntu / Kubuntu version:

• Debian:

   cat /etc/debian_version

• Ubuntu / Kubuntu:

  • cat /etc/issue

  • lsb-release -a (sau  cat /etc/lsb-release)

Change default browser:

•  update-alternatives – config x-www-browser or  update-alternatives – config www-browser 

Display (only) symbolic links with details

•  sudo find / -type l -print | xargs ls -lh

Display files/folder space usage

•  GUI: 
• FileLight, Disk Space Analyzer or gdmap  (Gnome) 
•  KDiskFree or KDirStat (KDE)

•   CLI:

• ncdu – interactive tool
• df -h
• du -bsh {FOLDER_NAME}
• du –max-depth=1 * | sort -n
• Find the top 10 biggest files: find . -type f -print0 | xargs -0 du -s | sort -n | tail -10 | cut -f2 | xargs -I{} du -sh {} 

Manage iso images and CD/DVD’s:

Create ISO imags from CD/DVD:


$ dd if=/dev/dvd of=dvd.iso # for dvd
$ dd if=/dev/cdrom of=cd.iso # for cdrom
$ dd if=/dev/scd0 of=cd.iso # if cdrom is scsi

These commands are useful for data CD/DVD images. For Audio CD’s there’s another (longer) story. (A simpler way would be to use specialized apps like: K3b, Acetoneiso, Brasero)

Create ISO image from folders:

$ mkisofs -v -o /tmp/user-folder.iso -R /home/user/user-folder

Write ISO images to CD/DVD:

• Find out your CDR/W SCSI address/device name:
  $ cdrecord -scanbus
• Write ISO image:
  $ cdrecord -v -dao dev=1,0,0 speed=8 file.iso
  (Where, -speed=XX : Specify writing speed, -v : Verbose output, -dev : The virtual SCSI ID of the writing device [discovered with the earlier command])

Mount / Umount / Format

•  sudo mount /dev/sdb1 /media/USB -t vfat  (sau ntfs / ext2/3/4) - montare partitie

•  sudo umount /dev/sdb1  - demontare partitie

•  sudo mkfs -t vfat /dev/sdb1  - formatare partitie

•  sudo eject /dev/sdb1 

Install software packages:

Subiectul este destul de bine detaliat aici. Pe scurt:

• .tar.gz / .tar.bz2:
  • extract sources:

    •  tar xzvf tarballname.tar.gz 

    •  tar xjvf tarballname.tar.bz2 

  • configure:

    •  cd tarballname 

    •  ./configure 

  • compile sources:

    •  make  [all]

    •  sudo checkinstall  [care inlocuieste:  sudo make install ]

• .deb:
  • graphic mode: double-click the file
  • console:

     sudo dpkg -i file.deb 

• .rpm:
  • conversion in .deb:

     sudo alien -k file.rpm  (after  sudo apt-get install alien , if not already installed)

  • install:

     sudo dpkg -i file.deb 

Calculate md5 checksums:

• for a string:

    echo -n "aaaaaa" | md5sum 

• for a file:

    md5sum file 

For Loop in Bash:

• The simple bash loop to do something with all files in the directory is:

   for f in * ; do echo $f ; done

  which just displays all files in this case.

  This is easy, what I usually need and often forget how to do it is to execute some action exact number of times. Something like simple for loop in C or Java. And there is an exact match for such loop in Bash too:

   for (( i=1 ; i

  I found another similar solution on the Internet today at spiralbound.net:

   for i in $(seq 1 100); do echo $i ; done

Renamefiles:

• UPPERCASE → lowercase

    rename ‘y/A-Z/a-z/’ * 

Empty existing files / Create new (temporary) files:

•  echo "" > file 

•  cp /dev/null file 

•  dd if=/dev/zero of=output.file bs=1 count=1 

•  cat /dev/null > your_file 

•  >filename

•  touch /tmp/newfilename

• command: mktemp which outputs something like: /tmp/tmp.yTfJX35144 script example:

    #!/bin/bash OUT=$(mktemp /tmp/output.XXXXXXXXXX) || { echo "Failed to create temp file"; exit 1; }  echo "Today is $(date)" >> $OUT 

Source: here and here.

Switch from openjdk to sunjdk

• Enable the Canonical Partner Software through the following steps:

  Go to Ubuntu Software Center.
  Click Edit.
  Click Software Sources.
  Switch to the Other Software tab and check Canonical Partners. This may take some time.

• In the Commandprompt, type the following sequence of commands:

  sudo apt-get update
  sudo apt-get install sun-java6-jre sun-java6-plugin
  sudo update-alternatives – config java