Localisation Localisation involves changing various parts of application output like display of dates , time , numbers , language etc according to the standards of the geographical region of a user. Localisation is an important feature of applications that targets users across the globe and not just one region. So here are a set of… Read More »
Part 2 26. Avoid direct SQL query , abstract it $query = "INSERT INTO users(name , email , address , phone) VALUES('$name' , '$email' , '$address' , '$phone')"; $db->query($query); //call to mysqli_query() The above is the simplest way way of writing sql queries and interacting with databases for operations like INSERT, UPDATE, DELETE etc. But… Read More »
Part 1 11. Do not gzip output in your application , make apache do that Thinking of using ob_gzhandler ? No dont do that. It doesnt make sense. Php is supposed to write your application. Dont worry about how to optimise data transfer between server and browser inside Php. Use apache mod_gzip/mod_deflate to compress content… Read More »
Php is used to write web applications which are online and publicly accessible. Therefore security is a fundamental necessity of these applications to keep the data safe and free from unauthorized access. Below are a bunch of simple tips/hacks/ideas to design your php applications to have better security. The Code 1. Avoid short tags If… Read More »
In this series we are going to look into some useful tips and techniques that can be used to improve and optimise your php code. Note that these php tips are meant for beginners and not those who are already using mvc frameworks etc. The Techniques 1. Do not use relative paths , instead define… Read More »
Like any other language php applications often need to execute system commands like they are run from the terminal/console/commandline. Php has multiple functions to do this task. Lets take a look at each of these 1. system “system() is just like the C version of the function in that it executes the given command and… Read More »
On linux , the list of locales installed on the system can be fetched through the terminal command locale -a : $ locale -a C C.UTF-8 en_AG en_AG.utf8 en_AU.utf8 en_BW.utf8 en_CA.utf8 en_DK.utf8 en_GB.utf8 en_HK.utf8 en_IE.utf8 en_IN en_IN.utf8 en_NG en_NG.utf8 en_NZ.utf8 en_PH.utf8 en_SG.utf8 en_US.utf8 en_ZA.utf8 en_ZM en_ZM.utf8 en_ZW.utf8 es_AR.utf8 es_BO.utf8 es_CL.utf8 es_CO.utf8 es_CR.utf8 es_DO.utf8 es_EC.utf8 es_ES.utf8… Read More »
This is a small script written in php that can fetch the whois information of an ip address from regional internet registries (RIR). Useful in finding information about ip address.
MAC Address The mac address (media access control address) or the hardware address or the ethernet address of an interface is a 48 bit number that looks like this : 00:1c:c0:f8:79:ee. Every machine connected to a network has a unique mac address that is used to deliver network packets to the correct machine. The mac… Read More »
On a Linux system, all network interfaces have a unique name that is shows up when you run the ifconfig command for example. The main network adapter often has the name eth0 or enp1s0 on linux systems. The ip address is configured using desktop gui tools, or through commands like ifconfig. If you are writing… Read More »
The function gettimeofday can be used to retrieve the total number of seconds and balance microseconds elapsed since EPOCH. Structure timeval looks like this : struct timeval { time_t tv_sec; /* seconds */ suseconds_t tv_usec; /* microseconds */ }; On Linux it can be done like this : /** * Get time difference in microseconds… Read More »
On Linux the header file sys/types.h provides the fixed sized integer data types like these : u_int8_t; u_int16_t; u_int32_t; On windows the header file stdint.h provides similar ones but with slightly different names , uint8_t etc. So if you are writing cross platform code you can get the same ones on windows as in a… Read More »
Theory The whois information of an ip address provides various details like its network, range, isp etc. This information is maintained by various regional registry servers. Read the wikipedia article on regional internet registries for more information. There are a total of 5 regional registries spanning various geographical regions of the world. For example if… Read More »
Socket programming with winsock This is a quick guide/tutorial to learning socket programming in C language on Windows. “Windows” because the code snippets shown over here will work only on Windows. The windows api to socket programming is called winsock. Sockets are the fundamental “things” behind any kind of network communications done by your computer…. Read More »
Handle multiple socket connections When writing server programs using sockets , it becomes necessary to handle multiple connections at a time , since a server needs to serve multiple clients. There are many ways to do so. On linux this can be done in various ways like forking , threading , select method etc. In… Read More »
Learn socket programming in C on the linux platform. Write socket servers and client programs in C.
Wxpython is the python port of wxwidgets gui library. On ubuntu wxpython can be installed from synaptic. On windows it can be downloaded from the website wxpython.org And here is a small program that pops up a simple window , to take a domain name and perform a whois for that domain. #!/usr/bin/python ''' GUI… Read More »
Whois A whois client is a program that will simply fetch the whois information for a domain/ip address from the whois servers. The code over here works according to the algorithm discussed here. A whois server runs a whois service on port 43 (whois port). We need to connect to this port with sockets and… Read More »
Php has a useful function called str_replace which can search and replace a certain string in another big string. However there is no such function in C. So I wrote up one for myself. Here is the code. /* * Search and replace a string with another string , in a string * */ char… Read More »
Local Ip address The local ip is the source ip in IP packets send out from a system. When the system is a part of a local area network then the local ip in most cases is something like 192.168.*.* . The network interface (eth0) is assigned an ip address of that range. However when… Read More »