This routine provides a means to find out in what areas your program
spends most of its time.
bytes of core.
Every virtual 10 milliseconds, the user's program counter (PC)
is subtracted and the result is multiplied by
and divided by 65536.
If the resulting value is less than
then the corresponding entry in
is NULL, profiling is disabled.
Zero is always returned.
Similar to a call in SVr4 (but not POSIX.1-2001).
cannot be used on a program that also uses
interval timers (see
True kernel profiling provides more accurate results.
Libc 4.4 contained a kernel patch providing a system call profil.