Nano is easy to use and lightweight command line text editor for Linux and UNIX systems. Nano text editor can use either the default settings or improve settings with customized nanorc-file. Here are some tips that can improve the usability of Nano. Changes can be made to nanorc file, either locally or to all users or options can be used as command line options.
First is good to check Nano compiled options, with command:
Sometimes it feels that many of the excellent and convenient command-line tools is forgotten, when they are replaced by graphical tools. A good example is the cal program, which is a command-line calendar to Linux and UNIX. It displays a simple calendar in text format.
Cal usage Displays current month calendar on console cal Output:
October 2009 Su Mo Tu We Th Fr Sa 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 Displays selected month and year calendar on console cal 11 2012 Output:
Sometimes you maybe have to handle files with a dash (-) as first character from Linux command line. It can be difficult, because the script “thinks” the marks after the dash are parameters.
So files which name begins with dash (-) can not be dealt with directly by typing the command and the file name, such as the following:
less -file-with-a-dash-as-first-character Files which name begins with dash (-) can be used as follows:
Today I started thinking that how cool is do some Google searches straight from command line. First I try to find some ready tricks from the Internet, but I couldn’t find quickly anything good. So I decide do a simple Bash function that can take Google search as parameter and open Firefox Browser (tab) with Google search. Sounds easy… :)
First we need Google search URL without search parameter and it looks like this:
Here is easy way add date and time to Linux terminal title. This trick works at least following terminals Gnome Terminal, xterm, urxvt, rxvt.
Simply type the following command line:
while sleep 1 ; do echo -ne '\033]2;'`date`'\007'; done &
Fedora team promises to bring to you the latest and greatest release of Fedora ever, Fedora 12! Many things are really changed and improved. Fedora 12 also brings lots of new packages.
Here is some highlights from Fedora 12 new stuff Optimized performance – 32-bit architecture software packages have been compiled with special optimization for the Intel Atom processors without losing compatibility with the overwhelming majority of CPUs. Smaller and faster updates – Fedora 12 uses yum-presto plugin as default. So update manager download only changes for packages. Improvements for graphics support – Introduces experimental 3D support for AMD Radeon HD 2400 and later graphics cards. To try it out, install the mesa-dri-drivers-experimental package. Better support for systems with multiple monitors. Bluetooth on-demand – Bluetooth services are automatically started when needed and stopped 30 seconds after last device use, reducing initial startup time and resource use when Bluetooth is not in active use. Better webcam support – Fedora 12 you can expect even better video quality, especially for less expensive webcams. Next-generation (Ogg) Theora video – Theora videos now deliver much better quality primarily via enhancements in the encoder without any change in the format Automatic reporting of crashes and SELinux issues – Abrt, a tool to help non-power users report crashes to Bugzilla with a few mouse clicks, is now enabled by default. And some higlights of new programs and packages on Fedora 12 Gnome 2.28 – Latest Gnome desktop release KDE 4.3 – Latest KDE desktop release Abrt – Tool for easy bug reporting Empathy – Default IM client Fedora Studio – Classify multimedia applications into subgroups for easy access NetBeans 6.7 – Latest NetBeans IDE Eclipse Galileo – Latest Eclipse Galileo Perl 6 PHP 5.3 Open Shared Root – Provides abilities to boot multiple linux systems with the same root filesystem GFS2 Clustered Samba – Support for clustered samba (including active/active configuration) over GFS2 using CTDB Here is Fedora 12 full release notes.
I think the most easiest way to upgrade Fedora 11 to Fedora 12 is program called preupgrade, which download needed packages from the server and then just reboot to installer and after install boot the new system. Of course it’s important backup your important files before upgrading.
Commands and screenshots of whole upgrading process First start with updating all Fedora 11 packages with following command as root yum update Install preupgrade as root yum install preupgrade Start preupgrade as root preupgrade Preupgrade information window
Looking Fedora 22/21 nVidia Drivers Install Guide?
I’ve tried this method in few Fedora 12 and Fedora 13 machine, and looks like it is working. Nouveau has been enabled by default starting from Fedora 11 and looks like nouveau cause some problems on Fedora 12 and Fedora 13, when try to use nVidia proprietary driver.
Note: nVidia proprietary drivers on Fedora 12 and Fedora 13 does not support older cards than GeForce 6 cards (except for some exceptions, check this comment).
Sometimes we need to delete files which content should disappear absolutely, completely and safely. Linux command rm just remove file and it’s still possible to dig out from the disk. Fortunately for Linux can be found in shred program that removes the files permanently. Shred command is easy and quickly to use cases when files need to deleted forever.
Shred command usage Create test file: echo "testing testing" > /tmp/test.txt Delete file with shred command: shred -v -n 25 -u -z /tmp/test.txt Output:
Few days ago I write about shred, which work fine for old systems, like EXT2, but not so nice with journaled file systems. Modern file systems need something more robust, like dd and srm (a secure replacement for rm). Unlike the standard rm, srm overwrites and rename the files before unlinking them. This makes it very hard to recovery of the data.
Create test file: echo "secure content" > /tmp/secure.txt dd and srm command usage Fill free space with zeroes (Use very carefully): dd if=/dev/zero of=/tmp/secure.txt Write buffered data from the memory out to disk sync Delete file with srm: # Basic example srm /tmp/secure.txt # US Dod compliant 7-pass overwrite. srm -D /tmp/secure.txt # US DoE compliant 3-pass overwrite. # Twice with a random pattern, finally with the bytes "DoE". # See http://cio.energy.gov/CS-11_Clearing_and_Media_Sanitization_Guidance.pdf for details. srm -E /tmp/secure.txt # OpenBSD compatible rm. Files are overwritten three times, first with the byte pattern # 0xff, then 0x00, and then 0xff again, before they are deleted. # Files with multiple links will be unlinked but not overwritten. srm -P /tmp/secure.txt Delete directory: srm -r /tmp/secure-directory Write buffered data from the memory out to disk sync Conclusion of commands # Create echo "secure content" > /tmp/secure.txt # Remove dd if=/dev/zero of=/tmp/secure.txt sync srm -D /tmp/secure.txt sync More info about options with commands:
PHP Command Line Interface (CLI) has not built-in coloring for script output, like example Perl language has (perldoc.perl.org/Term/ANSIColor.html). So I decided to make own class for adding colors on PHP CLI output. This class works only Bash shells. This class is easy to use. Just create new instance of class and call getColoredString function with string and foreground color and/or background color.
PHP Class for Coloring PHP Command Line (CLI) Scripts Output <?php class Colors { private $foreground_colors = array(); private $background_colors = array(); public function __construct() { // Set up shell colors $this->foreground_colors['black'] = '0;30'; $this->foreground_colors['dark_gray'] = '1;30'; $this->foreground_colors['blue'] = '0;34'; $this->foreground_colors['light_blue'] = '1;34'; $this->foreground_colors['green'] = '0;32'; $this->foreground_colors['light_green'] = '1;32'; $this->foreground_colors['cyan'] = '0;36'; $this->foreground_colors['light_cyan'] = '1;36'; $this->foreground_colors['red'] = '0;31'; $this->foreground_colors['light_red'] = '1;31'; $this->foreground_colors['purple'] = '0;35'; $this->foreground_colors['light_purple'] = '1;35'; $this->foreground_colors['brown'] = '0;33'; $this->foreground_colors['yellow'] = '1;33'; $this->foreground_colors['light_gray'] = '0;37'; $this->foreground_colors['white'] = '1;37'; $this->background_colors['black'] = '40'; $this->background_colors['red'] = '41'; $this->background_colors['green'] = '42'; $this->background_colors['yellow'] = '43'; $this->background_colors['blue'] = '44'; $this->background_colors['magenta'] = '45'; $this->background_colors['cyan'] = '46'; $this->background_colors['light_gray'] = '47'; } // Returns colored string public function getColoredString($string, $foreground_color = null, $background_color = null) { $colored_string = ""; // Check if given foreground color found if (isset($this->foreground_colors[$foreground_color])) { $colored_string .= "\033[" . $this->foreground_colors[$foreground_color] . "m"; } // Check if given background color found if (isset($this->background_colors[$background_color])) { $colored_string .= "\033[" . $this->background_colors[$background_color] . "m"; } // Add string and end coloring $colored_string .= $string . "\033[0m"; return $colored_string; } // Returns all foreground color names public function getForegroundColors() { return array_keys($this->foreground_colors); } // Returns all background color names public function getBackgroundColors() { return array_keys($this->background_colors); } } Colors class basic usage examples <?php // Create new Colors class $colors = new Colors(); // Test some basic printing with Colors class echo $colors->getColoredString("Testing Colors class, this is purple string on yellow background.", "purple", "yellow") . "\n"; echo $colors->getColoredString("Testing Colors class, this is blue string on light gray background.", "blue", "light_gray") . "\n"; echo $colors->getColoredString("Testing Colors class, this is red string on black background.", "red", "black") . "\n"; echo $colors->getColoredString("Testing Colors class, this is cyan string on green background.", "cyan", "green") . "\n"; echo $colors->getColoredString("Testing Colors class, this is cyan string on default background.", "cyan") . "\n"; echo $colors->getColoredString("Testing Colors class, this is default string on cyan background.", null, "cyan") . "\n"; Output:
This tip is really useful if you need/want to monitor multiple servers at the same time. This Tip works, as the tip, by which you can add the date and time the title of the Linux terminal, but it adds more usefull info to terminal title. Following bash one liner add hostname, date, time, uptime, users and load Average to Linux Terminal Title and updates it every second.
This trick works at least following terminals: Gnome Terminal, xterm, urxvt, rxvt.
Yum (Yellowdog Update Modified) is RPM Packet Management system for Fedora, CentOS, Red Hat, OpenSuse etc. Yum history (list, info, summary, repeat, redo, undo, new) commands is added on 3.2.25 version. So this works every Linux Distros, which uses yum 3.2.25 or newer. Yum history command is a really useful in situations where the need to example rollback latest yum activity or undelete some deletes or just see what is updated lately.
This is quick guide howto install PostgreSQL 8.4 (current stable 8.4.7) database server on CentOS, Fedora and Red Hat. Fedora 14, Fedora 13, CentOS 5.5 and Red Hat (RHEL) 5.5 has PostgreSQL 8.4 database server as default so extra repositories is not needed. Personally, I like to use Postgres own repositories, because the latest version of PostgreSQL may be quickly and easily installed. The following commands run as root and postgres user, so “su -” or “sudo -i” first.
This is a quick method to check with using cURL that Nginx/Apache (or any other web server) compression with Nginx ngx_http_gzip_module (gzip), Nginx google/ngx_brotli (br), Apache mod_brotli (br), Apache mod_gzip (gzip) and Apache mod_deflate (deflate) is working. Only the remote server headers are needed.
Check that the Nginx/Apache Compression is Working Get headers curl -s -I -H 'Accept-Encoding: br,gzip,deflate' https://www.if-not-true-then-false.com -s option silent, disable progress bar.
-I option which will make just HEAD request to server and get headers.
-H option add header for accept content-encoding br, gzip and deflate.
This is quick guide howto find files and directories quick and efficiently on Linux with locate command. Linux find command is outdated, slow and complicated to use, so locate command is much better option.
Locate basic usage find files and directories locate file # example locate httpd.conf locate path # example locate /X11/ Find (locate) ignore-case (not case sensitive) locate -i file # example locate -i netbeans Find (locate) only file name (basename) locate -b file # example locate -b shadow Limit locate output locate -l 100 file # example locate -l 50 conf Print number of found entries locate -c file # example locate -c conf Find (locate) with full file info Simply locate something and pipe output to ls command.
This is a very typical case, the need to create a temp file on the command line quickly. Opening editor, writing content, save file and quit editor is not the fastest possible way. A faster way is to use the cat command with the name of the file and write contents of the file and give the end-of-file character (Ctrl-D).
This is guide, howto create (or append to) text file without text editor on Linux shell / command line.
Are you looking LibreOffice 5.2/5.1/5.0 Install guide?
This is quick guide to install Apache OpenOffice 4.1.2 on Fedora 24/23/22/21/20/19/18/17/16/15/14/13/12, CentOS 7.2/6.8, Red Hat (RHEL) 7.2/6.8 with using Apache OpenOffice original RPM packages.
What’s new in Apache OpenOffice 4.1.2 release New Sidebar – The Sidebar makes better use of today’s widescreen displays than traditional toolbars Interoperability Improvements DrawObject Improvements/Enhancements Extensions Improvements/Enhancements Many resource leaks were fixed Check full feature list here.
This is a quick tip, howto find, query and list all available packages from a specific Yum repository/repositories on Fedora, CentOS, Red Hat (RHEL). This trick does not show the already installed packages from selected repository.
List All Repositories and Check Repository ID’s $ yum repolist Loaded plugins: dellsysidplugin2, refresh-packagekit repo id repo name status adobe-linux-i386 Adobe Systems Incorporated enabled: 17 fedora Fedora 12 - i386 enabled: 15,366 google Google - i386 enabled: 4 livna rpm.livna.org for 12 - i386 enabled: 3 rpmfusion-free RPM Fusion for Fedora 12 - Free enabled: 383 rpmfusion-free-updates RPM Fusion for Fedora 12 - Free - Updates enabled: 551 rpmfusion-nonfree RPM Fusion for Fedora 12 - Nonfree enabled: 124 rpmfusion-nonfree-updates RPM Fusion for Fedora 12 - Nonfree - Updates enabled: 228 updates Fedora 12 - i386 - Updates enabled: 4,587 repolist: 21,263 Query Available Packages From Selected YUM Repository Disable all repositories and then enable just selected repo.
I noticed that the Fedora Linux with KDE desktop, has reasonably poor support for laptop touchpad adjustment. For example, the KDE > System Settings > Keyboard & Mouse > Mouse options will not be able to enable vertical scrolling and touchpad tapping. So I decided to write this short guide, howto enable Touchpad vertical scrolling and tapping from command line without any GUI.
Enable Laptop Touchpad Vertical Scrolling Simply write following on command line:
