The best way to start working on an operating system is to write a simple legacy boot loader program and print a text or character on the screen. You could easily find resources online. Then obviously to proceed you must know some concepts about Operating Systems and also the hardware architecture. Initially you would be writing the code in assembly language to set up different directory tables and then switch to 32 bit protected mode from 16 bit real mode. Now you could code in higher level languages like C and link the objects of C and assembly together to form executable files. Now since the executable files does not need platform dependent relocations by loaders, they need not to contain unnecessary headers and must be in the correct formats (raw binary, elf, PE are some executable formats). You might need a cross compiler to compile to platform independent executable. Once you have reached this far, you could decide whether to move to 64 bit mode. You have to learn about various OS concepts like paging, process scheduling,etc. You might have to switch back and forth from assembly to higher level language as there are certain things only asm language could do. Also at this point bios services are unavailable. So you need to develop your own drivers. Once you understand how things works you could try on developing UEFI bootloaders too. I had also begun like you. And so far I have made this: The image file used for this program is not owned by me. ( actually my program could print any image file ). This is a simple UEFI bootloader which displays an image to the output screen. I am also in learning phase. There is this awesome site https://wiki.osdev.org/ which contains all resource you need to get started. goodluck.

Thanks for all your help. But I am using a real android device and there is no problem with the ip address or port. The program is working. The only problem was that the buffered writer is unable to write the complete string to the outputstream. I thought https://stackoverflow.com/questions/13426142/bufferedwriter-not-writing-everything-to-its-output-file&ved=2ahUKEwj8jNCOhJ3ZAhUIQI8KHVqdBoYQFjAAegQIExAB&usg=AOvVaw2uvC0jkgTnf-wWoz2wv5YY this will solve my problem but no it didn't Also localhost is actually my IP address of the server running on localmachine (xampp server).

Now corrected. Sorry.

Yes I have a PHP Server and an android client. The code starting from "Socket socket; ..... to Server.start()" works perfectly in plain java but when used in android application the BufferedWriter writes only first few character of the string to the output stream.

Is there a way to do this byte by byte. Suppose my file has to be of 500 bytes. I want first 250 bytes to be copied from "akon.mp3" and the next 250 bytes from "Coldplay.mp3". Is there a way to do this?

file1 and file2 are objects refrencing the resource "music.mp3" and "copied_file.mp3" respectively. An Inputstream is used to read the input file (music.mp3) and an Outputstream is used to write to the output file (copied_file.mp3). A while loop is used to read the bits of inputfile through inputstream and copy it to the outfile through outputstream until the size of output file is smaller than the input file and break out of the loop when both file have same size. This code is nothing but bit by bit copying of one file to another.

I am just currently doing some experimental stuffs . Please see if you could commit. https://github.com/rattesh

The idea here is to make a group of developers to work on commercial as well as experimental projects.

The first ever operating system I used was a Huawei Zem.