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  On Erlang's Syntax

I first planned to release this text as an appendix entry for Learn You Some Erlang, but considering this feels more like editorial content and not exactly something for a reference text, I decided it would fit better as a blog post. Many newcomers to Erlang manage to understand the syntax and program around it without ever getting used to it. I've read and heard many complaints regarding the syntax and the 'ant turd tokens' (a subjectively funny way to refer to ,, ; and .), how annoying...

   Erlang,Syntax,Error     2011-12-22 08:35:42

  A simple tutorial on Linux nohup command

In our daily work, there might be need to run some important program for hours or even days without being abruptly terminated. In such case, we may want to run the program with command nohup. nohup is the abbreviation of no hangup, i.e, don't hang up or terminate the process. This command will tell the process to ignore the system HUP signal. The HUP signal will be emitted when the terminal is exited or disconnected. Normally process will abort its execution when receiving this signal.  Bas...

   NOHUP,LINUX     2020-08-08 01:14:50

  Some useful Linux commands for teamwork

A small development team in the intranet will frequently transfer codes, share files. Here are some command we use frequently to release some of our work. They are not applicable to Windows users. 1. Output program execution output through GTalk. Sometimes we may need to send the program execution result and log to teammates for debugging using IM. These outputs are very troublesome to copy and send while in command line mode. So we could have a program called gpipe.py which can put GTalk as a p...

   Linux,NFS,GTalk,HTTP     2013-01-16 04:36:33

  What are some lesser known but useful Unix commands?

A few that come to mind, some less known, some more: xargs or parallel: run things in parallel, with lots of options sed and awk: more well-known but still super useful for processing text files, and faster than Python or Ruby m4: simple macro processor screen: powerful terminal multiplexing and session persistence yes: print a string a lot cal: nice calendar env: run a command (useful in scripts) look: find English words (or lines in a file) beginning with a string cut and paste and join: data...

   Linux,Unix,Command,Less used     2011-12-27 09:27:49

  System programming is still there

System programming is the practice of writing system software. System software lives at a low level, interfacing directly with the kernel and core system libraries. Your shell and your text editor, your compiler and your debugger, your core utilities and system daemons are all system software. But so are the network server, the web server, and the database. These components are entirely system software, primarily if not exclusively interfacing with the kernel and the C library. But nowadays more...

   System programming     2014-02-27 05:46:48

  Books for entry level C programmers

In computing, C is a general-purpose programming language initially developed by Dennis Ritchie between 1969 and 1973 at Bell Labs Its design provides constructs that map efficiently to typical machine instructions, and therefore it found lasting use in applications that had formerly been coded in assembly language, most notably system software like the Unix computer operating system.To learn C, we need to read many C books and have many practices. Here we summarize a list of C books which may h...

   C,Book,Beginning     2012-07-26 14:00:51

  How does GoLang know how many CPUs to use?

When running lscpu command on Linux, it will list the CPU info on the machine. Take one example where there is one CPU with 2 cores and each core has two threads which indicates there are 4 cores available. Now let's see how many cores GoLang program would identify. From output, NumCPU and GOMAXPROCS both output 4 which is expected. How does go runtime get this info, does it get it through similar command like lscpu or /proc/cpuinfo? Let's dig more in GoLang's source code. In runtim...

   GOLANG,CPU,NCPU     2020-12-29 23:22:15

  Oracle database to execute multiple statements at command line

Oracle database is now a mature and popular RDBMS which is used by lots of enterprises. With its evolution, many utilities and applications are developed around it as well. Now Oracle database also provides cloud support. As a DBA, managing Oracle database is daily routine work and some tools may be used frequently. One of them is sqlplus, the command line tool for executing SQL command. sqlplus is installed while the Oracle database is installed. To start sqlplus, one just needs to open a termi...

   ORACLE,ORACLE DATABASE,SQLPLUS     2016-12-09 20:11:28

  Most Pressed Keys and Programming Syntaxes

I switch between programming languages quite a bit; I often wondered what happens when having to deal with the different syntaxes, does the syntax allow you to be more expressive or faster at coding in one language or another. I dont really know about that; but what I do know what keys are pressed when writing with different programming languages. This might be something interesting for people who are deciding to select a programming language might look into, here is a post on the...

   Keyboard,Programming language,Hottest ke     2011-09-23 13:10:10

  A Peek Inside the Erlang Compiler

Erlang is a complex system, and I can’t do its inner workings justice in a short article, but I wanted to give some insight into what goes on when a module is compiled and loaded. As with most compilers, the first step is to convert the textual source to an abstract syntax tree, but that’s unremarkable. What is interesting is that the code goes through three major representations, and you can look at each of them. Erlang is unique among functional languages in its casual scop...

   Erlang,Peek,Erlang compiler     2012-02-08 10:12:04