My technical notes computer_science:software:linux:commands

computer_science:software:linux:commands:archive_all_files_in_a_directory

Anonymous (anonymous@undisclosed.example.com) — 2017-01-04T21:12:30+0200

Creating archives Using zip Use -e for encryption Use from -0 (none, archive only) to -9 (max) to set compression level zip /home//.zip -r /folder/to/archive -e -9 Using 7zip First verify that 7zip is installed sudo apt-get install p7zip-full

computer_science:software:linux:commands:cloning_a_hard_drive

Anonymous (anonymous@undisclosed.example.com) — 2015-03-12T10:37:41+0200

Cloning a Hard Drive The below command make a bit to bit copy of your hardriwe sudo dd if=/dev/sda of=/dev/sdb conv=sync,noerror With: * /dev/sda is the input(source drive) * /dev/sdb is the output(target drive) * sync,noerror must be used in combination, so dd will not stop if it encounter an error by reading the input.

computer_science:software:linux:commands:crypt_a_hard_drive_using_cryptsetup

Anonymous (anonymous@undisclosed.example.com) — 2015-03-12T10:38:31+0200

Crypt a hard drive using Cryptsetup Log as root and install cryptsetup thomas@pavillon-t546fr:~$ sudo -s root@pavillon-t546fr:~# apt-get install cryptsetup Load the needed Kernel modules using modprobe root@pavillon-t546fr:~# modprobe dm_crypt root@pavillon-t546fr:~# modprobe dm_mod

computer_science:software:linux:commands:delete_all_files_with_the_same_name_pattern_in_a_directory_and_its_subdirectories

Anonymous (anonymous@undisclosed.example.com) — 2015-03-12T10:39:11+0200

First use the command find to find all the files with a specific pattern. The -print0 options is useful for xargs. -print0 seperates each result of find with a 0 character. Then pipe the content of find to xargs. Use the -0 option of xargs, if your paths contain spaces characters.

computer_science:software:linux:commands:display_cpu_information

Anonymous (anonymous@undisclosed.example.com) — 2015-03-12T10:37:28+0200

GNU/Linux, commands for reading cpu information cpuinfo thomas@thomas-1005PE:~$ cat /proc/cpuinfo Output: processor : 0 vendor_id : GenuineIntel cpu family : 6 model : 28 model name : Intel(R) Atom(TM) CPU N450 @ 1.66GHz stepping : 10 microcode : 0x107 cpu MHz : 1000.000 cache size : 512 KB physical id : 0 siblings : 2 core id : 0 cpu cores : 1 apicid : 0 initial apicid : 0 fdiv_bug : no hlt_bug : no f00f_bug : no coma_bug : no fpu : yes fpu_exception : yes cpuid level : 10 wp : …

computer_science:software:linux:commands:display_only_the_line_n_of_a_text_file

Anonymous (anonymous@undisclosed.example.com) — 2015-03-12T10:39:38+0200

With X the number of the line to be displayed sed -n 'Xp' file.txt Display the 10th line of a text file: sed -n '10p' file.txt

computer_science:software:linux:commands:display_the_n_first_lines_of_a_text_file

Anonymous (anonymous@undisclosed.example.com) — 2015-03-12T10:39:25+0200

head -n file.txt Display only the first line of a text file: head -1 file.txt Display the 3 first lines of a text file: head -3 file.txt

computer_science:software:linux:commands:mount_.img_file

Anonymous (anonymous@undisclosed.example.com) — 2015-03-12T10:38:16+0200

.img files are not images of a partition, but of a whole disk. That means they start with a bootloader and a partition table. First, you have to find out the offset of the partition and mount it with the offset option of mount. fdisk -l /path/to/image

computer_science:software:linux:commands:play_mp3_from_the_command_line

Anonymous (anonymous@undisclosed.example.com) — 2015-03-12T10:40:06+0200

Play MP3 from the command line My favorite software is mpg123 because it is simple and doens't need a lot of resources. Start it with the -C parameter, so you will be able to enter command during the play. mpg123 -C /path/to/your/mp3/album/* Type h during the play to display the available commands.

computer_science:software:linux:commands:remount_a_partition_in_rw_mode_fstab_recovering

Anonymous (anonymous@undisclosed.example.com) — 2015-03-12T10:38:02+0200

Remount a partition in rw mode When you start Ubuntu in recovery mode, the system partition is mounted in read only mode. If you have an error in your /etc/fstab, you aren't able to modify it. The solution is to remount the system partition in read-write mode.

computer_science:software:linux:commands:remove_all_lines_of_a_text_file_except_the_ones_containing_a_keyword

Anonymous (anonymous@undisclosed.example.com) — 2015-03-12T10:39:54+0200

Delete all lines except the ones containing the word 'word' in the file 'filename' sed '/word/!d' filename.txt Delete all lines except the ones containing the word 'word' or the word 'word2' in the file filename sed '/word\|word2/!d' filename.txt

computer_science:software:linux:commands:remove_splashscreen_at_the_start_of_the_os

Anonymous (anonymous@undisclosed.example.com) — 2015-03-12T10:39:00+0200

Disabling Boot splashscreen This option is particularly useful to see the bootsequence or to enter the password of an encrypted harddrive during the boot process. Edit the /etc/default/grub file: sudo vi /etc/dafault/grub And change the value “

computer_science:software:linux:commands:truecrypt

Anonymous (anonymous@undisclosed.example.com) — 2015-03-12T10:38:45+0200

Useful truecrypt commands Opening a truecrypt volume that doen't have yet a filesystem truecrypt --filesystem=none /dev/sdg The truecrypt volume is then opened in /dev/mapper/truecrypt1 Once the volume is opened it is possible to format it: sudo mkfs.ntfs /dev/mapper/truecrypt1