macos - How to run C program on Mac OS X using Terminal?

Question

I am new to C. Here is my "Hello,world!" program.

#include <stdio.h>

int main(void)    
{
  printf("Hello, world!
");
  return 0;
}

After I try to run it using Terminal it says:

MacBook-Pro-MacBook:~ macbook$ /Users/macbook/Desktop/peng/Untitled1
-bash: /Users/macbook/Desktop/peng/Untitled1: Permission denied
MacBook-Pro-MacBook:~ macbook$ 

Why?

Answer 1

First save your program as program.c.

Now you need the compiler, so you need to go to App Store and install Xcode which is Apple's compiler and development tools. How to find App Store? Do a "Spotlight Search" by typing ⌘Space and start typing App Store and hit Enter when it guesses correctly.

App Store looks like this:

Xcode looks like this on App Store:

Then you need to install the command-line tools in Terminal. How to start Terminal? You need to do another "Spotlight Search", which means you type ⌘Space and start typing Terminal and hit Enter when it guesses Terminal.

Now install the command-line tools like this:

xcode-select --install

Then you can compile your code with by simply running gcc as in the next line without having to fire up the big, ugly software development GUI called Xcode:

gcc -Wall -o program program.c

Note: On newer versions of OS X, you would use clang instead of gcc, like this:

clang program.c -o program

Then you can run it with:

./program
Hello, world!

---

If your program is C++, you'll probably want to use one of these commands:

clang++ -o program program.cpp
g++ -std=c++11 -o program program.cpp
g++-7 -std=c++11 -o program program.cpp