Search for source codes of any programming languages has been demand since programmers and developers are being gifted 24/7 broadband internet with themselves they now dont have to go all those heavy reference books to page by page.

Among all code searching websites Google once again in search come top in this with its product Google Code Search that every body knows about.

Open Source code search engines act as repository of all documented source codes of various programming languages or various projects source codes open for public display, optimized highly to show results of only source codes. Despite of this there are some specialist search engines made specifically for code search. Some of them that I went through are;

Koders.com is one among leading search engine of open source code search. Display of results of source codes, I found on this site is least confusing and nicely formatted with codes in Grey background, display 3 lines below source code – Language source (C, C++ etc.), LOC (length of code, e.g. 43, 120 etc.) and reference document source along with active link to it.

Koders .com also provides Koders IDE plug-ins for developers and programmers for Visual Studio.NET 2003 and 2005 and Eclipse 3.0 and above. koders.com’s search panel will display in IDE itself as a toolbar component. one of the best use of code search is reusability of code and least probability of any syntax errors hence saving time.

Koders.com’ SmartSearch (TradeMarked) runs in the background then finds and recommends your existing source code in real time providing reusability of your own code, this is one thing that Microsoft, Sybase should think to inculcate and implement in their Visual Studio and PowerBuilder products respectively.

Codefetch.com on other hand shows results of source code along with related amazon ads, LOC as well with line no. within search results. This source code search engine provides all popular language along with most popular languages according to percentage of searched queries in codefetch.com. Codefetch.com is an affiliate of Open Technology Business Center.

QuickRef.org is another source code search engine but with Ajax. Its ajax enabled auto suggest feature in search box is best when one is looking for something that isn’t striking in mind at that point of time, like a name/ keyword of function/ method name you looking for etc.. you could end up with more options such as – (getelementByID.. getelementByClass.. ..getelementByName and more).

The searched or suggested keyword when clicked popup the centered window of freely available source document like W3C.org, cppreference.com or rubycentral.com for Ruby etc.

Codase.com is more detailed and extensive source code search engine that lets you search things other than just code like – function definition or method defined by class, class definition or even field defined in a class, class variable search, field reference search etc. According to Codase.com its beta release contains about 250 million lines of code in C, C++ and Java.

Other source code search engines includes – AllTheCode.com, gotAPI.com