In normal Bash script, $0 is the path to the script. However, when a script is sourced, such as
. a.sh
a.sh’s $0 does not give a.sh. How to get the a.sh inside a.sh?
Short answer: use ${BASH_SOURCE[0]}.
You can check this post for details and explanations: How to Get Bash Script’s Own Path.
When we design a system, we may want our systems to be consistency, scalability and so on. Currently, there are some famous consistency algorithms. How to understand them easily. 1, Paxos and its extensions 2, Replicated State Machine mechanisms 3, Quorum Welcome to adding other famous consistency algorithms and its understanding ;-) Reading text books…
Any GUI tools to crop PDF file margins on Linux? I use krop: http://arminstraub.com/computer/krop krop is a simple graphical tool to crop the pages of PDF files. To install krop on Fedora: # yum install krop Read more: How to merge multiple PDF files to a PDF on Linux? How to use vnc to connect…
In hadoop I need to skip mapper function and directly execute the reducer function. We doing this to improve hadoop performance, if the hadoop framework is used to analyze same data sets, then mapper’s output will be same for different kind of jobs. To save the redundant computation for same results, I am planning to…
I noticed that some guys’ screen console has a status bar with tab numbers. That will be very useful for 1) know you are using screen rather than a normal terminal. 2) which tab you are working in. Below is my ~/.screenrc: hardstatus alwayslastline hardstatus string ‘%{= kG}[ %{G}%H %{g}][%= %{=kw}%?%-Lw%?%{r}(%{W}%n*%f%t%?(%u)%?%{r})%{w}%?%+Lw%?%?%= %{g}][%{B}%Y-%m-%d %{W}%c %{g}]’ It…
Google Drive is nice cloud storage which provide document editing features. However, it does not yet provide a Linux client. I find a good third party tool that works with Google Drive on Linux very well: google-drive-ocamlfuse. The website of google-drive-ocamlfuse provides easy to follow instructions to install it. In this tutorial, we show a…
I find there are too many TCP segments retransmited in a Xen virtual machine. sudo netstat -s | grep segments 537559 segments received 558908 segments send out 3533 segments retransmited 2677 bad segments received. There are 4 VMs on a host which has 4 cores. The segment retransmision rate is too high. It finally turns…