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### Unleash Your Creativity Linux Programs for Drawing and Image Editing
By: [chabowski][1]
The following article is part of a series of articles that provide tips and tricks for Linux newbies or Desktop users that are not yet experienced with regard to certain topics. This series intends to complement the special edition #30 “[Getting Started with Linux][2]” based on [openSUSE Leap][3], recently published by the [Linux Magazine,][4] with valuable additional information.
![](https://www.suse.com/communities/blog/files/2017/11/DougDeMaio-450x450.jpeg)
This article has been contributed by Douglas DeMaio, openSUSE PR Expert at SUSE.
Both Mac OS or Window offer several popular programs for graphics editing, vector drawing and creating and manipulating Portable Document Format (PDF). The good news: users familiar with the Adobe Suite can transition with ease to free, open-source programs available on Linux.
Programs like [GIMP][5], [InkScape][6] and [Okular][7] are cross platform programs that are available by default in Linux/GNU distributions and are persuasive alternatives to expensive Adobe programs like [Photoshop][8], [Illustrator][9] and [Acrobat][10].
These creativity programs on Linux distributions are just as powerful as those for macOS or Window. This article will explain some of the differences and how the programs can be used to make your transition to Linux comfortable.
### Krita
The KDE desktop environment comes with tons of cool applications. [Krita][11] is a professional open source painting program. It gives users the freedom to create any artistic image they desire. Krita features tools that are much more extensive than the tool sets of most proprietary programs you might be familiar with. From creating textures to comics, Krita is a must have application for Linux users.
![](https://www.suse.com/communities/blog/files/2017/11/krita-450x267.png)
### GIMP
GNU Image Manipulation Program (GIMP) is a cross-platform image editor. Users of Photoshop will find the User Interface of GIMP to be similar to that of Photoshop. The drop down menu offers colors, layers, filters and tools to help the user with editing graphics. Rulers are located both horizontal and vertical and guide can be dragged across the screen to give exact measurements. The drop down menu gives tool options for resizing or cropping photos; adjustments can be made to the color balance, color levels, brightness and contrast as well as hue and saturation.
![](https://www.suse.com/communities/blog/files/2017/11/gimp-450x281.png)
There are multiple filters in GIMP to enhance or distort your images. Filters for artistic expression and animation are available and are more powerful tool options than those found in some proprietary applications. Gradients can be applied through additional layers and the Text Tool offers many fonts, which can be altered in shape and size through the Perspective Tool.
The cloning tool works exactly like those in other graphics editors, so manipulating images is simple and acurrate given the selection of brush sizes to do the job.
Perhaps one of the best options available with GIMP is that the images can be saved in a variety of formats like .jpg, .png, .pdf, .eps and .svg. These image options provide high-quality images in a small file.
### InkScape
Designing vector imagery with InkScape is simple and free. This cross platform allows for the creation of logos and illustrations that are highly scalable. Whether designing cartoons or creating images for branding, InkScape is a powerful application to get the job done. Like GIMP, InkScape lets you save files in various formats and allows for object manipulation like moving, rotating and skewing text and objects. Shape tools are available with InkScape so making stars, hexagons and other elements will meet the needs of your creative mind.
![](https://www.suse.com/communities/blog/files/2017/11/inkscape-450x273.png)
InkScape offers a comprehensive tool set, including a drawing tool, a pen tool and the freehand calligraphy tool that allows for object creation with your own personal style. The color selector gives you the choice of RGB, CMYK and RGBA using specific colors for branding logos, icons and advertisement is definitely convincing.
Short cut commands are similar to what users experience in Adobe Illustrator. Making layers and grouping or ungrouping the design elements can turn a blank page into a full-fledged image that can be used for designing technical diagrams for presentations, importing images into a multimedia program or for creating web graphics and software design.
Inkscape can import vector graphics from multiple other programs. It can even import bitmap images. Inkscape is one of those cross platform, open-source programs that allow users to operate across different operating systems, no matter if they work with macOS, Windows or Linux.
### Okular and LibreOffice
LibreOffice, which is a free, open-source Office Suite, allows users to collaborate and interact with documents and important files on Linux, but also on macOS and Window. You can also create PDF files via LibreOffice, and LibreOffice Draw lets you view (and edit) PDF files as images.
![](https://www.suse.com/communities/blog/files/2017/11/draw-450x273.png)
However, the Portable Document Format (PDF) is quite different on the three Operating Systems. MacOS offers [Preview][12] by default; Windows has [Edge][13]. Of course, also Adobe Reader can be used for both MacOS and Window. With Linux, and especially the desktop selection of KDE, [Okular][14] is the default program for viewing PDF files.
![](https://www.suse.com/communities/blog/files/2017/11/okular-450x273.png)
The functionality of Okular supports different types of documents, like PDF, Postscript, [DjVu][15], [CHM][16], [XPS][17], [ePub][18] and others. Yet the universal document viewer also offers some powerful features that make interacting with a document different from other programs on MacOS and Windows. Okular gives selection and search tools that make accessing the text in PDFs fluid for how users interact with documents. Viewing documents with Okular is also accommodating with the magnification tool that allows for a quick look at small text in a document.
Okular also provides users with the option to configure it to use more memory if the document is too large and freezes the Operating System. This functionality is convenient for users accessing high-quality print documents for example for advertising.
For those who want to change locked images and documents, its rather easy to do so with LibreOffice Draw. A hypothetical situation would be to take a locked IRS (or tax) form and change it to make the uneditable document editable. Imagine how much fun it could be to transform it to some humorous kind of tax form …
And indeed, the skys the limit on how creative a user wants to be when using programs that are available on Linux distributions.
![2 votes, average: 5.00 out of 5](https://www.suse.com/communities/blog/wp-content/plugins/wp-postratings/images/stars_crystal/rating_on.gif)
![2 votes, average: 5.00 out of 5](https://www.suse.com/communities/blog/wp-content/plugins/wp-postratings/images/stars_crystal/rating_on.gif)
![2 votes, average: 5.00 out of 5](https://www.suse.com/communities/blog/wp-content/plugins/wp-postratings/images/stars_crystal/rating_on.gif)
![2 votes, average: 5.00 out of 5](https://www.suse.com/communities/blog/wp-content/plugins/wp-postratings/images/stars_crystal/rating_on.gif)
![2 votes, average: 5.00 out of 5](https://www.suse.com/communities/blog/wp-content/plugins/wp-postratings/images/stars_crystal/rating_on.gif)
(
_**2** votes, average: **5.00** out of 5_
)
_You need to be a registered member to rate this post._
Tags: [drawing][19], [Getting Started with Linux][20], [GIMP][21], [image editing][22], [Images][23], [InkScape][24], [KDE][25], [Krita][26], [Leap 42.3][27], [LibreOffice][28], [Linux Magazine][29], [Okular][30], [openSUSE][31], [PDF][32] Categories: [Desktop][33], [Expert Views][34], [LibreOffice][35], [openSUSE][36]
--------------------------------------------------------------------------------
via: https://www.suse.com/communities/blog/unleash-creativity-linux-programs-drawing-image-editing/
作者:[chabowski ][a]
译者:[译者ID](https://github.com/译者ID)
校对:[校对者ID](https://github.com/校对者ID)
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译,[Linux中国](https://linux.cn/) 荣誉推出
[1]:https://www.suse.com/communities/blog/author/chabowski/
[2]:http://www.linux-magazine.com/Resources/Special-Editions/30-Getting-Started-with-Linux
[3]:https://en.opensuse.org/Portal:42.3
[4]:http://www.linux-magazine.com/
[5]:https://www.gimp.org/
[6]:https://inkscape.org/en/
[7]:https://okular.kde.org/
[8]:http://www.adobe.com/products/photoshop.html
[9]:http://www.adobe.com/products/illustrator.html
[10]:https://acrobat.adobe.com/us/en/acrobat/acrobat-pro-cc.html
[11]:https://krita.org/en/
[12]:https://en.wikipedia.org/wiki/Preview_(macOS)
[13]:https://en.wikipedia.org/wiki/Microsoft_Edge
[14]:https://okular.kde.org/
[15]:http://djvu.org/
[16]:https://fileinfo.com/extension/chm
[17]:https://fileinfo.com/extension/xps
[18]:http://idpf.org/epub
[19]:https://www.suse.com/communities/blog/tag/drawing/
[20]:https://www.suse.com/communities/blog/tag/getting-started-with-linux/
[21]:https://www.suse.com/communities/blog/tag/gimp/
[22]:https://www.suse.com/communities/blog/tag/image-editing/
[23]:https://www.suse.com/communities/blog/tag/images/
[24]:https://www.suse.com/communities/blog/tag/inkscape/
[25]:https://www.suse.com/communities/blog/tag/kde/
[26]:https://www.suse.com/communities/blog/tag/krita/
[27]:https://www.suse.com/communities/blog/tag/leap-42-3/
[28]:https://www.suse.com/communities/blog/tag/libreoffice/
[29]:https://www.suse.com/communities/blog/tag/linux-magazine/
[30]:https://www.suse.com/communities/blog/tag/okular/
[31]:https://www.suse.com/communities/blog/tag/opensuse/
[32]:https://www.suse.com/communities/blog/tag/pdf/
[33]:https://www.suse.com/communities/blog/category/desktop/
[34]:https://www.suse.com/communities/blog/category/expert-views/
[35]:https://www.suse.com/communities/blog/category/libreoffice/
[36]:https://www.suse.com/communities/blog/category/opensuse/

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### System Logs: Understand Your Linux System
![chabowski](https://www.suse.com/communities/blog/files/2016/03/chabowski_avatar_1457537819-100x100.jpg)
By: [chabowski][1]
The following article is part of a series of articles that provide tips and tricks for Linux newbies or Desktop users that are not yet experienced with regard to certain topics). This series intends to complement the special edition #30 “[Getting Started with Linux][2]” based on [openSUSE Leap][3], recently published by the [Linux Magazine,][4] with valuable additional information.
This article has been contributed by Romeo S. Romeo is a PDX-based enterprise Linux professional specializing in scalable solutions for innovative corporations looking to disrupt the marketplace.
System logs are incredibly important files in Linux. Special programs that run in the background (usually called daemons or servers) handle most of the tasks on your Linux system. Whenever these daemons do anything, they write the details of the task to a log file as a sort of “history” of what theyve been up to. These daemons perform actions ranging from syncing your clock with an atomic clock to managing your network connection. All of this is written to log files so that if something goes wrong, you can look into the specific log file and see what happened.
![](https://www.suse.com/communities/blog/files/2017/11/markus-spiske-153537-300x450.jpg)
Photo by Markus Spiske on Unsplash
There are many different logs on your Linux computer. Historically, they were mostly stored in the /var/log directory in a plain text format. Quite a few still are, and you can read them easily with the less pager. On your freshly installed openSUSE Leap 42.3 system, and on most modern systems, important logs are stored by the systemd init system. This is the system that handles starting up daemons and getting the computer ready for use on startup. The logs handled by systemd are stored in a binary format, which means that they take up less space and can more easily be viewed or exported in various formats, but the downside is that you need a special tool to view them. Luckily, this tool comes installed on your system: its called journalctl and by default, it records all of the logs from every daemon to one location.
To take a look at your systemd log, just run the journalctl command. This will open up the combined logs in the less pager. To get a better idea of what youre looking at, see a single log entry from journalctl here:
```
Jul 06 11:53:47 aaathats3as pulseaudio[2216]: [pulseaudio] alsa-util.c: Disabling timer-based scheduling because running inside a VM.
```
This individual log entry contains (in order) the date and time of the entry, the hostname of the computer, the name of the process that logged the entry, the PID (process ID number) of the process that logged the entry, and then the log entry itself.
If a program running on your system is misbehaving, look at the log file and search (with the “/” key followed by the search term) for the name of the program. Chances are that if the program is reporting errors that are causing it to malfunction, then the errors will show up in the system log. Sometimes errors are verbose enough for you to be able to fix them yourself. Other times, you have to search for a solution on the Web. Google is usually the most convenient search engine to use for weird Linux problems
![](https://www.suse.com/communities/blog/files/2017/09/Sunglasses_Emoji-450x450.png)
. However, be sure that you only enter the actual log entry, because the rest of the information at the beginning of the line (date, host name, PID) is unnecessary and could return false positives.
After you search for the problem, the first few results are usually pages containing various things that you can try for solutions. Of course, you shouldnt just follow random instructions that you find on the Internet: always be sure to do additional research into what exactly you will be doing and what the effects of it are before following any instructions. With that being said, the results for a specific entry from the systems log file are usually much more useful than results from searching more generic terms that describe the malfunctioning of the program directly. This is because many different things could cause a program to misbehave, and multiple problems could cause identical misbehaviors.
For example, a lack of audio on the system could be due to a massive amount of different reasons, ranging from speakers not being plugged in, to back end sound systems misbehaving, to a lack of the proper drivers. If you search for a general problem, youre likely to see a lot of irrelevant solutions and youll end up wasting your time on a wild goose chase. With a specific search of an actual line from a log file, you can see other people who have had the same log entry. See Picture 1 and Picture 2 to compare and contrast between the two types of searching.
![](https://www.suse.com/communities/blog/files/2017/11/picture1-450x450.png)
Picture 1 shows generic, unspecific Google results for a general misbehavior of the system. This type of searching generally doesnt help much.
![](https://www.suse.com/communities/blog/files/2017/11/picture2-450x450.png)
Picture 2 shows more specific, helpful Google results for a particular log file line. This type of searching is generally very helpful.
There are some systems that log their actions outside of journalctl. The most important ones that you may find yourself dealing with on a desktop system are /var/log/zypper.log for openSUSEs package manager, /var/log/boot.log for those messages that scroll by too fast to be read when you turn your system on, and /var/log/ntp if your Network Time Protocol Daemon is having troubles syncing time. One more important place to look for errors if youre having problems with specific hardware is the Kernel Ring Buffer, which you can read by typing the dmesg -H command (this opens in the less pager as well). The Kernel Ring Buffer is stored in RAM, so you lose it when you reboot your system, but it contains important messages from the Linux kernel about important events, such as hardware being added, modules being loaded, or strange network errors.
Hopefully you are prepared now to understand your Linux system better! Have a lot of fun!
--------------------------------------------------------------------------------
via: https://www.suse.com/communities/blog/system-logs-understand-linux-system/
作者:[chabowski]
译者:[译者ID](https://github.com/译者ID)
校对:[校对者ID](https://github.com/校对者ID)
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译,[Linux中国](https://linux.cn/) 荣誉推出
[1]:https://www.suse.com/communities/blog/author/chabowski/
[2]:http://www.linux-magazine.com/Resources/Special-Editions/30-Getting-Started-with-Linux
[3]:https://en.opensuse.org/Portal:42.3
[4]:http://www.linux-magazine.com/

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Wake up and Shut Down Linux Automatically
============================================================
### [banner.jpg][1]
![time keeper](https://www.linux.com/sites/lcom/files/styles/rendered_file/public/banner.jpg?itok=zItspoSb)
Learn how to configure your Linux computers to watch the time for you, then wake up and shut down automatically.
[Creative Commons Attribution][6][The Observatory at Delhi][7]
Don't be a watt-waster. If your computers don't need to be on then shut them down. For convenience and nerd creds, you can configure your Linux computers to wake up and shut down automatically.
### Precious Uptimes
Some computers need to be on all the time, which is fine as long as it's not about satisfying an uptime compulsion. Some people are very proud of their lengthy uptimes, and now that we have kernel hot-patching that leaves only hardware failures requiring shutdowns. I think it's better to be practical. Save electricity as well as wear on your moving parts, and shut them down when they're not needed. For example, you can wake up a backup server at a scheduled time, run your backups, and then shut it down until it's time for the next backup. Or, you can configure your Internet gateway to be on only at certain times. Anything that doesn't need to be on all the time can be configured to turn on, do a job, and then shut down.
### Sleepies
For computers that don't need to be on all the time, good old cron will shut them down reliably. Use either root's cron, or /etc/crontab. This example creates a root cron job to shut down every night at 11:15 p.m.
```
# crontab -e -u root
# m h dom mon dow command
15 23 * * * /sbin/shutdown -h now
```
```
15 23 * * 1-5 /sbin/shutdown -h now
```
You may also use /etc/crontab, which is fast and easy, and everything is in one file. You have to specify the user:
```
15 23 * * 1-5 root shutdown -h now
```
Auto-wakeups are very cool; most of my SUSE colleagues are in Nuremberg, so I am crawling out of bed at 5 a.m. to have a few hours of overlap with their schedules. My work computer turns itself on at 5:30 a.m., and then all I have to do is drag my coffee and myself to my desk to start work. It might not seem like pressing a power button is a big deal, but at that time of day every little thing looms large.
Waking up your Linux PC can be less reliable than shutting it down, so you may want to try different methods. You can use wakeonlan, RTC wakeups, or your PC's BIOS to set scheduled wakeups. These all work because, when you power off your computer, it's not really all the way off; it is in an extremely low-power state and can receive and respond to signals. You need to use the power supply switch to turn it off completely.
### BIOS Wakeup
A BIOS wakeup is the most reliable. My system BIOS has an easy-to-use wakeup scheduler (Figure 1). Chances are yours does, too. Easy peasy.
### [fig-1.png][2]
![wake up](https://www.linux.com/sites/lcom/files/styles/floated_images/public/fig-1_11.png?itok=8qAeqo1I)
Figure 1: My system BIOS has an easy-to-use wakeup scheduler.
[Used with permission][8]
### wakeonlan
wakeonlan is the next most reliable method. This requires sending a signal from a second computer to the computer you want to power on. You could use an Arduino or Raspberry Pi to send the wakeup signal, a Linux-based router, or any Linux PC. First, look in your system BIOS to see if wakeonlan is supported -- which it should be -- and then enable it, as it should be disabled by default.
Then, you'll need an Ethernet network adapter that supports wakeonlan; wireless adapters won't work. You'll need to verify that your Ethernet card supports wakeonlan:
```
# ethtool eth0 | grep -i wake-on
Supports Wake-on: pumbg
Wake-on: g
```
* d -- all wake ups disabled
* p -- wake up on physical activity
* u -- wake up on unicast messages
* m -- wake up on multicast messages
* b -- wake up on broadcast messages
* a -- wake up on ARP messages
* g -- wake up on magic packet
* s -- set the Secure On password for the magic packet
man ethtool is not clear on what the p switch does; it suggests that any signal will cause a wake up. In my testing, however, it doesn't do that. The one that must be enabled is g -- wake up on magic packet, and the Wake-on line shows that it is already enabled. If it is not enabled, you can use ethtool to enable it, using your own device name, of course:
```
# ethtool -s eth0 wol g
```
```
@reboot /usr/bin/ethtool -s eth0 wol g
```
### [fig-2.png][3]
![wakeonlan](https://www.linux.com/sites/lcom/files/styles/floated_images/public/fig-2_7.png?itok=XQAwmHoQ)
Figure 2: Enable Wake on LAN.
[Used with permission][9]
Another option is recent Network Manager versions have a nice little checkbox to enable wakeonlan (Figure 2).
There is a field for setting a password, but if your network interface doesn't support the Secure On password, it won't work.
Now you need to configure a second PC to send the wakeup signal. You don't need root privileges, so create a cron job for your user. You need the MAC address of the network interface on the machine you're waking up:
```
30 08 * * * /usr/bin/wakeonlan D0:50:99:82:E7:2B
```
Using the real-time clock for wakeups is the least reliable method. Check out [Wake Up Linux With an RTC Alarm Clock][4]; this is a bit outdated as most distros use systemd now. Come back next week to learn more about updated ways to use RTC wakeups.
Learn more about Linux through the free ["Introduction to Linux" ][5]course from The Linux Foundation and edX.
--------------------------------------------------------------------------------
via: https://www.linux.com/learn/intro-to-linux/2017/11/wake-and-shut-down-linux-automatically
作者:[Carla Schroder]
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校对:[校对者ID](https://github.com/校对者ID)
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[1]:https://www.linux.com/files/images/bannerjpg
[2]:https://www.linux.com/files/images/fig-1png-11
[3]:https://www.linux.com/files/images/fig-2png-7
[4]:https://www.linux.com/learn/wake-linux-rtc-alarm-clock
[5]:https://training.linuxfoundation.org/linux-courses/system-administration-training/introduction-to-linux
[6]:https://www.linux.com/licenses/category/creative-commons-attribution
[7]:http://www.columbia.edu/itc/mealac/pritchett/00routesdata/1700_1799/jaipur/delhijantarearly/delhijantarearly.html
[8]:https://www.linux.com/licenses/category/used-permission
[9]:https://www.linux.com/licenses/category/used-permission

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### [Fedora Classroom Session: Ansible 101][2]
### By Sachin S Kamath
![](https://fedoramagazine.org/wp-content/uploads/2017/07/fedora-classroom-945x400.jpg)
Fedora Classroom sessions continue this week with an Ansible session. The general schedule for sessions appears [on the wiki][3]. You can also find [resources and recordings from previous sessions][4] there. Here are details about this weeks session on [Thursday, 30th November at 1600 UTC][5]. That link allows you to convert the time to your timezone.
### Topic: Ansible 101
As the Ansible [documentation][6] explains, Ansible is an IT automation tool. Its primarily used to configure systems, deploy software, and orchestrate more advanced IT tasks. Examples include continuous deployments or zero downtime rolling updates.
This Classroom session covers the topics listed below:
1. Introduction to SSH
2. Understanding different terminologies
3. Introduction to Ansible
4. Ansible installation and setup
5. Establishing password-less connection
6. Ad-hoc commands
7. Managing inventory
8. Playbooks examples
There will also be a follow-up Ansible 102 session later. That session will cover complex playbooks, roles, dynamic inventory files, control flow and Galaxy.
### Instructors
We have two experienced instructors handling this session.
[Geoffrey Marr][7], also known by his IRC name as “coremodule,” is a Red Hat employee and Fedora contributor with a background in Linux and cloud technologies. While working, he spends his time lurking in the [Fedora QA][8] wiki and test pages. Away from work, he enjoys RaspberryPi projects, especially those focusing on software-defined radio.
[Vipul Siddharth][9] is an intern at Red Hat who also works on Fedora. He loves to contribute to open source and seeks opportunities to spread the word of free and open source software.
### Joining the session
This session takes place on [BlueJeans][10]. The following information will help you join the session:
* URL: [https://bluejeans.com/3466040121][1]
* Meeting ID (for Desktop App): 3466040121
We hope you attend, learn from, and enjoy this session! If you have any feedback about the sessions, have ideas for a new one or want to host a session, please feel free to comment on this post or edit the [Classroom wiki page][11].
--------------------------------------------------------------------------------
via: https://fedoramagazine.org/fedora-classroom-session-ansible-101/
作者:[Sachin S Kamath]
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[1]:https://bluejeans.com/3466040121
[2]:https://fedoramagazine.org/fedora-classroom-session-ansible-101/
[3]:https://fedoraproject.org/wiki/Classroom
[4]:https://fedoraproject.org/wiki/Classroom#Previous_Sessions
[5]:https://www.timeanddate.com/worldclock/fixedtime.html?msg=Fedora+Classroom+-+Ansible+101&iso=20171130T16&p1=%3A
[6]:http://docs.ansible.com/ansible/latest/index.html
[7]:https://fedoraproject.org/wiki/User:Coremodule
[8]:https://fedoraproject.org/wiki/QA
[9]:https://fedoraproject.org/wiki/User:Siddharthvipul1
[10]:https://www.bluejeans.com/downloads
[11]:https://fedoraproject.org/wiki/Classroom