Author Archives: daniel.kreling

Create patches with git format-patch

Git has a wonderful tool that allows you to create patches of the commits in the tree of your project: git format-patch.


 $ git format-patch [<options>] [<since> | <revision-range>]

More information can be seen via man page:

$ git format-patch -h


$ man git format-patch

For example:

$ git format-patch -N

This command generates one .patch file for each of the N commits on the top of your tree. Example:

$ git format-patch -1

Generates a .patch file for the commit on the top of your tree. Increase the number to get one file per commit (for the top 3 commits, use ‘-3’).

To apply the patch, use

$ git am [your-patch].patch



npm/yarn: live-server installation issue

Executive summary:


$ live-server
zsh: command not found: live-server SOLUTION: $ export PATH=$PATH:/home/user/.yarn/bin/


Today my attempt to install the live-server package in a Linux Mint Sylvia (Ubuntu Xenial) box using yarn failed. The installation went just fine, with just some info messages:

$ yarn global add live-server
yarn global v1.3.2
[1/4] Resolving packages...
[2/4] Fetching packages...
warning Pattern ["object-assign@latest"] is trying to unpack in the same destination "/home/dbkreling/.cache/yarn/v1/npm-object-assign-4.1.1-2109adc7965887cfc05cbbd442cac8bfbb360863" as pattern ["object-assign@^4.1.0","object-assign@^4"]. This could result in a non deterministic behavior, skipping.
info fsevents@1.1.3: The platform "linux" is incompatible with this module.
info "fsevents@1.1.3" is an optional dependency and failed compatibility check. Excluding it from installation.
[3/4] Linking dependencies...
[4/4] Building fresh packages...
success Installed "live-server@1.2.0" with binaries:
- live-server
Done in 1.98s

Cool! And then..

$ live-server
zsh: command not found: live-server



Digging it further I found it (no pun intended) hidden in my home directory:

$ sudo find / -name "*live-server*"
[sudo] password for dbkreling:
find: ‘/run/user/1000/gvfs’: Permission denied

Looking at my PATH, I had no .yarn directory whatsoever, so this is what I got:


After adding ~/.yarn/bin to my $PATH I had no more problems  to run it:

$ export PATH =$PATH:$HOME/.yarn/bin


Multiple refs on .git/config

Recently I was trying to push my latest patch to Gerrit when I suddenly started to see an error (“suddenly” as I did not relate any recent changes made that could cause the error. More on it next…)

[09:51:10] sdk@f25:~/tools-devel$ git push review
error: dst ref refs/for/master receives from more than one src.
error: failed to push some refs to 'ssh://'
error: dst ref refs/for/master receives from more than one src.
error: failed to push some refs to 'ssh://'

This error is caused by multiple refs tree within refs/remotes/origin. So go to your project’s .git/config file and search for a [remote "origin"] section there and do what you need to do to get just one ref only.

Make sure you read some more on git remote in previous posts:

Git remove remote branch from repo via CLI
Selecting remote repository on git



VIM buffer commands

Commands from vim buffers can take long to get into our brains. Practice will lead to perfection… eventually.

Here are some tips to get them into memory faster:

Editor commands:    
  :e filename - Edit a file an existing file in a new buffer
  :sp filename - Open a file in a new buffer and split window
  :vs or :vsp Open a file in a new buffer and split window vertically 
  ctrl+ws - Split window to work in two places of the same file
  ctrl+wv - Split window vertically (and work in the same file)

Navigation commands:
  :bnext (or :bn) - go to next buffer
  :bprev (of :bp) - go to previous buffer
  :bd - delete a buffer (close a file)
  ctrl+ww - switch between windows
  ctrl+wq - Quit a window

With pictures to decorate this post:


Open up a new file called ‘example1’


With ‘example1’ open, type in ‘:vs example2’ to vertically split the window and edit a new file ‘example2‘. It will open up a new buffer to the left of ‘example1’


From the ‘example2’ buffer, type in ‘:sp example3’ to horizontally split the screen and edit a new file ‘example3‘. It will open a new buffer above ‘example2’


All three buffers displayed. Use CTRL-W+W to cycle through them.



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)



Git remove remote branch from repo via CLI

Quick shot: To remove a remote branch on your git repo:

git push [remote-name] --delete [branch-name]


dkreling@dkreling:~/RobotFramework|devel ✔ ⟫ git branch -r

dkreling@dkreling:~/RobotFramework|devel ✔ ⟫ git push origin --delete teste [8:46:33]
remote: Updating references: 100% (1/1)
To ssh://dkreling@:/RobotFramework.git
 - [deleted] test