How to put files with spaces in names into HDFS?

I got this error when I tried to save a file with a space in its name into HDFS: $ hdfs dfs -put -f “/home/u1/testa/test a” “/u1/testa/test a” put: unexpected URISyntaxException while the HDFS seems allow spaces in its file names: https://hadoop.apache.org/docs/r2.7.3/hadoop-project-dist/hadoop-common/filesystem/model.html . How to achieve the effect of saving the files with spaces in […]

How to get an environment variable in Python?

In Python, how to get an environment variable? In Python, you may use this piece of code to get an environment variable: os.environ.get(‘ENV_MIGHT_EXIST’) or this piece of code: os.getenv(‘ENV_MIGHT_EXIST’) It will return None if the environment variable is not present. Reference and for more ways, please check https://www.systutorials.com/dtivl/13/how-to-get-an-environment-variable?show=80#answer-80 . Answered by zma.

Where to download an old release package of Hadoop?

The download page of Hadoop http://hadoop.apache.org/releases.html only contains several recent release packages. I would like to download some old release packages such as Hadoop 2.5.0 which is not available anymore on the release page. Where to download a copy of the old release? You can download the old release packages of Hadoop on the http://archive.apache.org […]

How to sort all files recursively by modification time in a directory on Linux?

How to sort all the files in a directory and subdirectories recursively by modification time on Linux? You can make use of find (GNU find, or plus stat), sort and sed together to achieve recursively sort files by modification time: find . -type f -printf ‘%T@ %pn’ | sort -k 1 -n | sed ‘s/^[^ […]

How to make WordPress regenerate the thumbnails after I changing the media aspects?

I recently changes the media aspects. The problem is that the existing thumbnails are not changed to the new aspects. How to make WordPress regenerate the thumbnails after I changing the media aspects? The “Regenerate Thumbnails” works like a charm for me: https://wordpress.org/plugins/regenerate-thumbnails/ . It allows you to regenerate your thumbnails after changing the thumbnail […]

How to convert between Simplified Chinese and Traditional Chinese characters in text files on Linux?

How to convert between Simplified Chinese and Traditional Chinese characters in text files on Linux from command line? You can use opencc to convert between Traditional Chinese and Simplified Chinese: https://github.com/BYVoid/OpenCC For example, to transfer a file in simplified Chinese sc.txt to traditional Chinese: opencc -i sc.txt -o tc.txt -c zhs2zht.ini The authors also provide […]

How to un-trust a computer that I have trusted with iOS 7 device?

How to un-trust a computer that I have trusted with iOS 7 device, such as iPhone? You can delete the Lockdown folder to reset the trust/un-trust status of iPhones. Apple provides tutorials for Max OS X and Windows at: http://support.apple.com/kb/TS5335 (archived) . If you are using Linux, the Lockdown folder is: /var/lib/lockdown Answered by Lucy.

How to use LVM groups with libvirt

libvirt uses files for VM images by default under /var/lib/libvirt/images/. LVM is a convenient tool for managing VM images. How to use LVM groups with libvirt? This post discusses the method to add LVM groups as a storage pool for libvirt: http://ailoo.net/2011/02/use-a-lvm-volume-group-with-libvirt/ For a general introduction of the storage management in libvirt, please check: http://libvirt.org/storage.html […]