Compiling and running code

Build an executable from our source code and run it.

Compilation

We can compile our C program using a program known as gcc.

First, open a terminal and make sure you are in the directory which contains your C source file (e.g. main.c). If not, use the cd command to get there.

After that, run this command:

gcc main.c

(replacing main.c with the name of your C source file).

Running the binary

Assuming you are on a Unix-based system or are emulating a Unix system, gcc will produce a binary called a.out. You can run your program using this command:

./a.out

Sometimes, gcc can output a file marked without execute permissions. This means that you will not be able to run your program unless you change the file permission attributes. You can fix that with a simple command:

chmod +rwx a.out

Choosing the name of the output binary

gcc allows us to choose the name of the binary file it outputs (instead of a.out). We can do this by specifying the -o flag when compiling:

gcc main.c -o outputbinary

This will compile our program into the outputbinary file.

Then, to run the outputbinary program:

./outputbinary

Compiling and running the code

We can compile the source file and execute the binary in a single command. The command below will compile the code and only if is successful, will execute the program:

gcc main.c && ./a.out

If you renamed your program’s output binary, say, to mycoolprogram, you would use:

gcc main.c -o mycoolprogram && ./mycoolprogram