Category Archives: Ubuntu

Mount HFS+ as R/W without a MacOS

If you created a usb flash drive using MacOS, chances are you might have an HFS+ (journaled) file system device in your hands.

NOTE: If you do have a Mac sitting around, try this before.

In case you do not have access to a Mac, you may have to tweak a little to get your device working normally.

When you try to use your usb stick in Linux, you will have it mounted as a Read Only file system.

/dev/sdb3 on /media/dbkreling/dbkusb type hfsplus (ro,nosuid,nodev,uhelper=udisks2)

A filesystem check (fsck) did not work for me:

$ sudo fsck /dev/sdb3
fsck from util-linux 2.20.1
fsck: fsck.hfsplus: not found
fsck: error 2 while executing fsck.hfsplus for /dev/sdb3

Let’s install it then. The name of the package is hfsprogs:

$ sudo apt-get install hfsprogs

Preparing to unpack .../hfsprogs_332.25-11_amd64.deb ...
Unpacking hfsprogs (332.25-11) ...
Processing triggers for man-db ( ...
Setting up hfsprogs (332.25-11) ...

Now let’s try fsck again:

$ sudo fsck -f /dev/sdb3
fsck from util-linux 2.20.1
** /dev/sdb3
** Checking HFS Plus volume.
** Checking Extents Overflow file.
** Checking Catalog file.
** Checking Catalog hierarchy.
** Checking Extended Attributes file.
** Checking volume bitmap.
** Checking volume information.
** The volume dbkusb appears to be OK.

Nice! Making progress… Then create a mounting point for it, other than the default one (without this step, I could not make it work, so make sure you do it):

$ mkdir /mnt/usb

Make sure the flash drive is unmounted and remount it at the new mount point, forcing r/w mode:

$ sudo umount /dev/sdb3
$ sudo mount -t hfsplus -o force,rw /dev/sdb3 /mnt/usb/
$ mount
/dev/sdb3 on /mnt/usb type hfsplus (rw,force)




Fast search your project with ag – the silver searcher

“Ag” is a powerful search tool that can come in handy in many situations. Use it to replace your grep searches.

NOTE: some exploration is still to be made, so if you are a pro, share your knowledge with the peasants 😉

Ubuntu 16:
$ sudo apt install silversearcher-ag

Fedora 26:
$ sudo dnf install the_silver_search


$ ag -h


Recursively search for PATTERN in PATH.
 Like grep or ack, but faster.

 ag -i foo /bar/

If you give it a try, let us know


Solve VirtualBox Guest Additions Autorun issue on Fedora 26 and Debian 9

Install VirtualBox Guest Additions on Fedora 26

NOTE: If your user does not have root rights, add it to the root group (probably ‘wheel’).

$ dnf update kernel*

$ sudo reboot

After it boots up again, the guest additions should be up and running, and you should be able to see your desktop on full screen.

Install VirtualBox Guest Additions on Debian Stretch (9)

Insert the VBoxGuestAdditions CD image from the ‘Devices’ menu. (I had a lot of mount issues with this). It should automatically mount and automatically run.

If it does not autorun, you have to manually run the script. First solve any root permissions you may have (adding $USER to the visudo file should solve it: insert a line right after ‘root’ with your user name). Then go to /media/cdrom0 or wherever your VBoxGuestAddition.iso is mounted and issue:

# bash

It should run seamlessly if everything is OK.

You are welcome to share your comments.


List gpg keys in your system

1.1. RPM based distros (RHEL, CentOS, Fedora)


$ sudo rpm --import repomd.xml.key


$ rpm -q gpg-pubkey|sort

Getting info:

rpm -qi  | grep Summary   

(or without the ‘grep’ part to view full info of the key package)

To remove:

sudo rpm -e --allmatches 


[root chip ~]# rpm -q gpg-pubkey|sort
[root chip ~]# rpm -e --allmatches gpg-pubkey-8df56d05-3e828977
[root chip ~]# rpm -q gpg-pubkey|sort

1.2 Debian / Ubuntu

$ gpg --list-keys user_ID


$ gpg --list-keys
pub   2048R/E5****A4 2015-01-12
uid                  IBM Software Development Kit for Linux on Power
sub   2048R/F2*****9 2015-01-12

pub   4096R/78C*****4 2016-02-11
uid                  IBM SDK for Linux on Power (The IBM Software Development Kit for Linux on Power is a free Eclipse-based Integrated Development Environment) <>
sub   4096R/B3*****0 2016-02-1

Add a gpg-key in your environment:

After you get the .gpg file, you need to 'add-apt-key' it into your keyring. Here:
$ sudo apt-key add .gpg

Don’t forget:
$ sudo apt-get update


Installing clang on RHEL/CentOS and Ubuntu

For RHEL and CentOS:

1) Install EPEL repository (read here on how to install it)

2) Install clang package:
$ sudo yum install clang

For Ubuntu 16.04:

1) Install clang packages:
$ sudo apt-get install clang libclang-dev

2) Create a symlink to libclang:
$ cd /usr/lib/-linux-gnu
$ sudo ln -s

$ cd /usr/lib/powerpc64le-linux-gnu
$ sudo ln -s