How to Synchronize Thunderbird Calendar and Address Book with Office365 Exchange Online using ActiveSync

Thunderbird is a nice email client available on Linux and Windows. With the Lightning plugin, Thunderbird can support calendar functions well. Exchange is a widely used email and calendar/address book service software. Office 365 provide the cloud version of Exchange named Office 365 Exchange Online. Although Exchange Online provide IMAP for synchronizing emails, it provides […]

How to Statically Link OCaml Programs

Static linking is preferred for some cases although it has its own various problems. Static building/linking is not always possible for some languages on some platform. For OCaml, the answer to this question is yes. In this post, we will introduce 2 methods to statically linking OCaml: static linking with runtime glibc required and static […]

How to enlarge root partition and filesystem size of cloud Linux VM at runtime without rebooting Linux

It is common that the root disk space is not enough when running a Virtual Machine in the cloud such as Amazon Web Service (AWS). The cloud storage usually provides tools or facilities to enlarge a virtual disk size. However, to make the Linux recognize and and use the enlarged disks without rebooting the OS, […]

How to set up Insync to synchronize Google Drive and Google Docs files in Ubuntu 18.04 Linux

Google Drive is a nice cloud storage service. It provides a suite of nice online document spreadsheet and slide editors Google Docs, Google Sheets and Google Slides. The collaborative editing and full history tracking features of Google Docs are excellent. Google Drive gives 16GB free storage which is pretty much larger compared to other free […]

How to resize a virtual disk of KVM

I test it for qcow2 format. Other formats are TBA. qemu-img resize kvm1.qcow2 +20G cp kvm1.qcow2 kvm1-orig.qcow2 virt-resize –expand /dev/sda1 kvm1-orig.qcow2 kvm1.qcow2 Reference: https://fatmin.com/2016/12/20/how-to-resize-a-qcow2-image-and-filesystem-with-virt-resize/ I test it for qcow2 format. Other formats are TBA. qemu-img resize kvm1.qcow2 +20G cp kvm1.qcow2 kvm1-orig.qcow2 virt-resize –expand /dev/sda1 kvm1-orig.qcow2 kvm1.qcow2 Reference: https://fatmin.com/2016/12/20/how-to-resize-a-qcow2-image-and-filesystem-with-virt-resize/ Answered by harryxiyou.

How to list start and end sectors of a partition by parted in Linux?

How to list start and end of a partition by the sectors in parted on Linux? The default behavior seems be listing the start and end by bytes in parted. # parted /dev/sdc print Model: Innostor IS888 ext. HDD (scsi) Disk /dev/sdc: 2000GB Sector size (logical/physical): 512B/512B Partition Table: gpt Disk Flags: Number Start End […]

Why I cannot login remote server with its root

# ssh root@192.168.122.96 root@192.168.122.96’s password: Permission denied, please try again. Do according to [1]. NOTE: on Ubuntu, remember to restart ssh service like this “sudo restart ssh”. [1] https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/6/html/v2v_guide/preparation_before_the_p2v_migration-enable_root_login_over_ssh Answered by harryxiyou.

How to apply the Email sort order to all folders in Evolution?

Evolution’s default Email sort order is not very convenient, at least to me. How to apply the settings of sort order for a folder to all folders in Evolution? Manually setting the email sort order for each dir is tedious. Evolution has a function to “apply the same view settings to all folder” so that […]

How to remove newline characters from a string in C++?

How to remove newline characters from a string in C++? For example, a string like line 1 line 3 line 4 should be converted to line 1line 3line 4 In short, use this code snippet: input.erase(std::remove(input.begin(), input.end(), ‘\n’), input.end()); std::remove() shifts all elements that are equal to the value n by moving the elements in […]

How can I login without password and run command in server at a local machine remotely?

Login without PWD is fast and efficient. Running commands in server from local machine also have these benefits. login without PWD: add PC A’s public key to PC B’s authorized keys. > a@A:~> cat .ssh/id_rsa.pub | ssh b@B ‘cat >> .ssh/authorized_keys’ > b@B’s password: Run command remotely ssh root@MachineB “ls” NOTE: running commands remotely is […]

How to judge whether its STDERR is redirected to a file in a Bash script on Linux?

Within a Bash script, how to judge whether its STDERR is redirected to a file in Bash on Linux? For example, ./script.sh /tmp/log 2>&1 Can script.sh detect that its STDERR is redirected? Knowing the destination file is better. To test whether a script’s STDERR (or STDOUT) is redirected to a file, check by [[ -f […]