open, creat, read, write, lseek and close

Are they all primitive?




*Another Question: is there a different between a system call, and an i/o system call?

Gosh, this sounds a lot like homework...

This could be someone reading a book and getting lost in the terminology. So I will give the poster the benefit of doubt and assume that the rule against homework questions is not being broken.

Yes those 6 functions are usually considered "primitive". Over the years the open system call has gained more power. creat can now be implemented as a call to open. That is the only questionable one among the group. If you look at all of the system calls you will see that a lot of them are involved in i/o. You could use the term "i/o system calls" to describe that set. But you would need some other term like, "non i/o system calls" for stuff like gettimeofday, setuid, etc. Reasonable minds could disagree over which class gets certain system calls like exit and exec.