Ah yes, C programming at its finest—writing a C program whose sole purpose is to create and execute a bash script. Because why use one language when you can use two? This developer is basically using a nuclear submarine to cross a puddle.
The irony is delicious. The code claims "Programming in C is easy" while demonstrating the most convoluted way possible to print "hello world"—by having C generate a bash script with execute permissions, which then prints the message. It's like building a machine that builds a machine that ties your shoelaces.
Four system calls when a single printf would do. This is the programming equivalent of taking a flight from New York to Boston with a layover in Tokyo.