How to get the date and time from another timezone in Python? You may use the pytz library. Example usage as follows. $ python3 Python 3.8.2 (default, Jul 16 2020, 14:00:26) >>> from datetime import datetime >>> import pytz >>> >>> print(datetime.now(pytz.timezone(‘Europe/Amsterdam’)).strftime(‘%Y-%m-%d %H:%M:%S %Z%z’)) 2020-08-09 15:50:00 CEST+0200 >>>
How to enable user themes in Ubuntu 18.04?
Posted onThe way for Ubuntu 17 to installing the gnome-shell-extensions package does not work any more for Ubuntu 18.04. How to enable user themes in Ubuntu 18.04? The updated gnome-shell-extensions package actually adds the User Theme extension back. You can use that. First, install the package sudo apt install gnome-shell-extensions Second, log out and login again
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How to get date and time using date command from another timezone in Linux?
Posted ondate command on Linux gets the date and time in the system timezone. But how to get date and time using date command from another timezone in Linux? You can make date print the time of another timezone by setting the TZ environment variable. For example, export TZ=Hongkong; date Sat Dec 1 09:39:13 HKT 2018
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How to detach a docker container to be a running daemon?
Posted onIf I quite a docker instanced (invoking /bin/bash) by Ctrl+d, the docker container is closed. How to detach a docker container to be a running daemon without closing it? Docker has a detach sequence, which, by default, is Ctrl-p + Ctrl-q. If the docker detach sequence is overridden by the –detach-keys=”<sequence>” flag, you need to
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Fixing the huge emoji icons in Unbuntu 18.04 for Thunderbird
Posted onIn Ubuntu 18.04, Thunderbird shows huge emoji icons in the email list. The emoji covers other text and is several lines higher and wider than other charactors. How to solve it? This is likely caused by the fonts. Find out the *emoji* fonts installed in your system by sudo apt list *emoji* and remove those
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How to change the logo shown during booting in Ubuntu?
Posted onHow to change the logo shown during booting in Ubuntu? I originally installed Ubuntu MATE 18.04. But I am using GNOME 3 now by replacing the DE. But the log shown during booting is still Ubuntu MATE’s. How to change it to another one? It is plymouth the application that manages the “splash” screen during
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GNOME 3 "Natural scrolling" mouse option does not work
Posted onIn GNOME 3 “Settings” -> “Devices” -> “Mouse & Touchpad”, after setting “Natural scrolling” to On, the scrolling is still as the same before (non-natural). How to fix this? This is likely related to the X11 driver. Remove the xorg-x11-drv-synaptics driver if it is installed. And install the xorg-x11-drv-libinput driver if it is not installed.
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How to install GNOME 3 in Ubuntu MATE 18.04?
Posted onHow to install the GNOME 3 (gnome-shell) desktop environment in Ubuntu MATE 18.04? To install gnome3 to Ubuntu, install these packages sudo apt install gnome-session gdm3 ubuntu-desktop During installation, the installation tools will let you choose the default display manager. You may choose gdm3. Then reboot you Ubuntu Linux and gdm3 will be shown. Click
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Installing Zlib from Source Code in Ubuntu Linux
Posted onZlib is a popular open-source compression library used by many software applications to compress and decompress data. While it can be installed in Ubuntu using the apt package manager, you may need to install it from the source code if the version available in the Ubuntu repositories is outdated or if you need to customize
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How to add Chinese input method to Unbuntu 18.04?
Posted onHow to add Chinese input method, such as Pinyin, to Unbuntu 18.04? To input Chinese, first install an input method framework. Here, we use fcitx. Then you need to input the Pinyin input method. You may use fcitx-sunpinyin. Put them all together $ sudo apt-get install fcitx fcitx-sunpinyin After that, set the default input method
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Thunderbird Addons to Make Thunderbird Easier to Use
Posted onThunderbird is powerful and feature rich. But different users have different needs and it is not feasible to include all features into the base software, where a plugin system shines. Thunderbird, similar to Firefox from Mozilla, supports addons/plugins and has a large ecosystems. Here, we will introduce several addons to Thunderbird that make Thunderbird easier
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How to test a file or directory exists in Go?
Posted onHow to test a path (a file or directory exists) in golang? In Bash, the [ -e ] tests can test whether a file or a directory exist. What are the corresponding Go ways for the test? You can use the `os.Stat()` and `os.IsNotExist()` standard libraries functions together to test whether a file or a
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File system Inode flags: difference between FS_IOC_GETFLAGS and FS_IOC_FSGETXATT
Posted onWhat is the difference between FS_IOC_GETFLAGS and FS_IOC_FSGETXATTR ioctl commands? What flags do both return? The comment in fs.h is clear enough to explain itself. In short, FS_IOC_GETFLAGS was for ext2/ext3 only, and FS_IOC_FSGETXATTR is a generic FS level interface. Full comment as follows for your reference (source): /* * Inode flags (FS_IOC_GETFLAGS / FS_IOC_SETFLAGS)
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Port forwarding on local host
Posted onI am trying to forward UDP port 500 to 2500 on local host, but can’t get this to work – I have run: iptables -t nat -A PREROUTING -p udp -d 192.168.1.10 –dport 500 -j DNAT –to-destination 192.168.1.10:2500 iptables -A FORWARD -p udp -d 192.168.1.10 –dport 2500 -j ACCEPT where 192.168.1.10 is the IP of
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How to convert a string to lower case in Python?
Posted onHow to convert a string to lower case in Python? For example: “Abc” -> “abc” “BBB” -> “bbb” “abc” -> “abc” You can use the string.lower() method of Python: string.lower(s) Return a copy of s, but with upper case letters converted to lower case. Example: $ python Python 2.7.5 (default, Apr 11 2018, 07:36:10) [GCC
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System Call Tracking without ptrace,strace,etc.
Posted onHow could I log system calls made by another process without using current built in functions like ptrace, strace, audit etc. I think two options are intercepting the system call table, and another is modifying the entry_64.s file. I want to output these system calls to a file. Can’t find any suggestions on this anywhere.
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How to filter bbpress content in WordPress
Posted onIn WordPress, we can filter the post content by adding a filter to the_content: add_filter('the_content', 'inline_markdown_pre_process_shortcode2', 7); But how to filter the content for bbpress contents? bbpress topic and reply (they are separated) content have their own filters: bbp_get_topic_content and bbp_get_reply_content. For example, add_filter(‘bbp_get_topic_content’, ‘my_plugin_custom_bbp_function’); add_filter(‘bbp_get_reply_content’, ‘my_plugin_custom_bbp_function’); function my_plugin_custom_bbp_function($content) { return ‘my_plugin_custom_bbp_function processed: ‘.$content; }
Call a Function by Its Name as a String in PHP
Posted onIn PHP, it is possible to call a function by its name as a string. This can be useful when the name of the function is not known until runtime, or when the name of the function is stored in a variable or retrieved from a database or other external source. To call a function
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Handling Sparse Files on Linux
Posted onSparse files are common in Linux/Unix and are also supported by Windows (e.g. NTFS) and macOSes (e.g. HFS+). Sparse files uses storage efficiently when the files have a lot of holes (contiguous ranges of bytes having the value of zero) by storing only metadata for the holes instead of using real disk blocks. They are
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gdb like step by step debugger for Python
Posted onAny good debugger for Python that is like gdb so that the code can be executed step by step for debugging purpose? You might check pdb. You can debug a program such as prog.py by invoking it through pdb: python -m pdb prog.py Common gdb commands can be found in pdb: (Pdb) h Documented commands
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