C++11 std::unique_ptr as semantic value in Bison C++ mode
Recently I spent some time to write a DSL ( domain specific Language) lexer and parser. Without double flex, bison (C++) will be used. Bison ( version 3.0.2/3.04) generally support…
Geocoding 40 millions US addresses totally free with PostGIS 2.1 on debian 8
Postgis 2.1 ( on debian 8) make geocoding US addresses ( about 40 Million ) quite easy, and it is totally free! Thanks for the PostGIS and PostGRESQL open source…
socat introduction
While searching a command line to write something into a UNIX Domain Socket, I found this great tool called socat which is similar to netcat/samplicator but has more features. The…
How to see all network traffic in (KVM) VM
if your NIC ( eth0) of the KVM (VM) is on the host device br0,and you want to see all the network traffics, what you can do is: on the…
systemctl cheatsheat
Systemd template and instance (@) from: https://wiki.archlinux.org/index.php/systemd Note: Some unit names contain an @ sign (e.g. name@string.service): this means that they are instances of a template unit, whose actual…
how to update default session-manager for GDM3
I like to use gnome-flashback mode which is like old gnome2 desktop, but I keep on forgetting this how to set the default login session, so put notes here. sudo…
lxc /dev increased from 100k to 500k and some other minor issues
While using lxc container, one annoying thing is the disk size of /dev was limited to 100k by default, with some hardware ( with lxc.autodev=1), the /dev could go beyond…
what is application container, OS container , VM
Application container: docker OS containers: LXC, OpenVZ, Linux VServer, BSD Jails, Solaris Zones VM: KVM, VMware, VirtualBox Good images from https://blog.risingstack.com/operating-system-containers-vs-application-containers/ References https://blog.risingstack.com/operating-system-containers-vs-application-containers/ http://www.itworld.com/article/2915530/virtualization/containers-vs-virtual-machines-how-to-tell-which-is-the-right-choice-for-your-enterprise.html https://www.flockport.com/supercharge-lxc-with-btrfs/
Linux device driver: A fix for insmod invalid module format
How to fix “insmod invalid module format” for a out-of-tree linux device driver or kernel module? If your kernel source tree matched your run time kernel, it turns out that…
convert PDF 1.1 to other versions
Someone asked me to convert pdf 1.1 to 1.4, I googled around, and found this: http://stackoverflow.com/questions/3450616/convert-pdf-from-version-1-1-to-1-4-or-higher Pdf 1.1 is forward compatible with pdf 1.4. Everything in pdf 1.1 will work…
