Does gettimeofday() on macOS use a system call?

Question

I expect that gettimeofday() will call a system call to do the work of actually getting the time. However, running the following program

#include &l         


        

Answer 1

The use of dtrace instead of dtruss will clear your doubt. gettimeofday() is itself a system call. You can see this system call getting called if you run dtrace script.

You can use following dtrace script "dtrace1.d"

syscall:::entry
/ execname == "foo" / 
{
}

(foo is the name of your executable)

to run above dtrace use: dtrace -s dtrace1.d

and then execute your program to see all system call used by your program