How do system calls work?

Question

I understand that a user can own a process and each process has an address space (which contains valid memory locations, this process can reference). I know that a process can c

Answer 1

Yes, your understanding absolutely right, a C program can call direct system call, when that system call happens it can be a series of calls till assembly Trap. I think immensely your understanding can help a newbie.Check this code in which I am calling "system" system call.

#include < stdio.h  >    
#include < stdlib.h >    
int main()    
{    
    printf("Running ps with "system" system call ");    
    system("ps ax");    
    printf("Done.\n");    
    exit(0);    
}