Once you comment out #Defaults requiretty on /etc/sudoers you get this error if you don't allow user to use command without prompting for password. The fix is easy thought. Allow user to use the command without prompting for password in /etc/sudoers file.
This is generally enforced by having Defaults requiretty in the /etc/sudoers. No panic, there is an easy fix! Comment out #Defaults requiretty on /etc/sudoers
The problem with installing pdftk on Centos 7 is that if has dropped support for libgcj. But you can install to package to install pdftk on centos7.
Use this command ln -s <real folder> <link folder> to create symbolic link. With this command <link folder> will actually contain everything <real folder> have.
Instead of typing a long command, use a Bash rc (keyboard shortcut) on Linux / Unix / Mac OS X to speed up your day to day task.
On Updating Ubuntu OS sometime the Unity Desktop doesn't fully load. This short and sweet article shows how to reinstall Ubuntu Unity Desktop without loosing your sleep.
XML Lint is a command line tool that allows you to format and Parse Badly Formed XML Data. Instruction on installing XMLLint on Linux (Ubuntu, Centos, Fedora, openSUSE) operating system.
Learn how to use setfacl and getfacl to set and view the files and folder permission. Using setfacl will ensure all the files and folder will have a permission specified by setfacl.
Find out how to copy files and folder from your local computer using linux to remote linux server with different port number other than 80 or 8080.