int main(int argc, char *argv[])
{
    puts("Hello world.");

    return 0;
}

chmod x (file name.c)

./(file name.c)

./file.c: line 1: syntax error near unexpected token `('
./file.c: line 1: `int main (int argc, char *argv[])'

sudo apt-get install gcc

gcc -Wall -o file file.c

./file

$ /usr/bin/tcc -run - <<EOF
> #include <stdio.h>
> int main()
> {
>    printf("Hello Worldn");
>    return 0;
> }
> EOF
Hello World

gcc file.c

#include <stdio.h>
int main(){
   printf("Hello World");
   return 0;
}