Programming in C on Android

C is a powerful General Purpose Programming Language. Learning C could be beneficial as it is one of the basic but powerful language, there are several powerful tools which had been developed using C. The Python interpreter is written in C language known as CPython, Linux  OS was built using C, Android Kernels , MacOS and even Crunch a pentest password word list generator tool is built using C language.

So to start with C programming, a newbie must have an Integrated Development Environment(IDE).

It would be so difficult to write in a notepad. IDE can make things much simpler, makes every task like Compiling, Linking, Debugging easy to perform. Without an IDE it would be difficult for developer to mange a project.

There are several IDE's for Windows, but the two popular ones are listed below with print screen:

1. Dev C++

Dev C++

Download link: https://www.bloodshed.net/devcpp.html 

2. Codeblocks

Codeblocks

 Download link: http://www.codeblocks.org/downloads/binaries#windows

But the colleges and Universities prefer using Borland Turbo C++

Borland Turbo C++

Download link: https://anonymousfiles.io/xc5B2G2b/

But when we come to Android Devices. There are very few IDE's that follow C rules of Dennis Ritchie. Hence, this blog focuses on how to start programming on Android devices in C. 

There are several ways to install Borland Turbo C++ IDE on Android. But in this post, we'll use Termux (an Android terminal emulator and Linux environment app that works directly with no rooting or setup required). 

Screenshot

Welcome Screen

 Play Store Link: https://play.google.com/store/apps/details?id=com.termux&hl=en_IN

Installation:

1. Install Termux from Play Store.

2. On first start, Termux will take to start as dependencies are being installed.

      Note: Do not interrupt while installing on first start.

3. After you get the screen as shown in screenshot. Type or Copy-Paste the Command in Termux below.

     Note: During Installation of any script here, if you are prompted 'Do you want to continue[Y/n]', Enter Y and press Enter/Send on keyboard.

    $ apt-get update

Output should be something like this

4. For installing  vim(editor) for terminal. Use

    $ pkg install vim

vim had been successfully installed 

5. The last step for installation is to install the clang(compiler).

    $ pkg install clang

clang after installation

The Installation is complete.

Now, we must know how to use these applications/tools.

How to use:

Before starting you should be aware of basic terminal commands, some of them are as follows

 i.  make directory:

     Syntax: mkdir directory_name

     example: mkdir C_Programs

 ii. list: 

     This command is used to list of files in the directory in which we are working.

     example: ls   

     (this will print all the files in current directory)

iii. change directory:

     Syntax: cd directory_name

     example: cd C_Programs

     (this will change my directory which we have created named as C_Programs)

iv. remove file:

     Syntax: rm file_name

     example: rm Hello.C

     (Hence, Hello.C  C file will be removed)

 v. touch command:

     This command will create a empty file.

      Syntax: touch file_name

      example: touch temp.c

      (Self Explanatory)

vi. vim commands:      

:e filename	Open filename for edition
:w	Save file
:q	Exit Vim
:q!	Quit without saving
:x	Write file (if changes has been made) and exit
:sav filename	Saves file as filename
.	Repeats the last change made in normal mode

Steps:

1. Create a directory in terminal.(This step can be skipped)

     using mkdir command.

     $ mkdir C_Programs

     

    

    ls command can be used to view the directory.

2. Changing directory to C_Program:

    $ cd C_Programs

/ is optional 

3. Creating an empty c file:

    $ touch temp.c

The empty file can be viewed using ls command

4. Using vim editor to write a C program:

   $ vim temp.c

Press Send/Enter/Return key to edit and write a program

5. Editing the file:

After Editing

Empty C File

    To Save the edited file, Press Esc, then type :x to save and exit the file.

6. Compiling The file:

    To compile the file use gcc command followed by the filename then -o(output file)  followed by <output_filename>

    Syntax: gcc file_name -o ouput_file_name

     

     $ gcc temp.c -o temp

File has been successfully compiled 

  If you encounter any error there's is something wrong with the program.

  You can view compiled file using  ls command.

temp green colored file is the compiled file

7. Executing the compiled file:

    To execute the compiled file simply type ./filename

    Syntax: ./file_name

    Example:./temp

  

Successfully Executed..

Explore C in Termux.