profil(3) -- Linux man page
NAMEprofil - execution time profile
DESCRIPTIONThis routine provides a means to find out in what areas your program spends most of its time. The argument buf points to bufsiz bytes of core. Every virtual 10 milliseconds, the user's program counter (PC) is examined: offset is subtracted and the result is multiplied by scale and divided by 65536. If the resulting value is less than bufsiz, then the corresponding entry in buf is incremented. If buf is NULL, profiling is disabled.
RETURN VALUEZero is always returned.
BUGSprofil cannot be used on a program that also uses ITIMER_PROF itimers.
CONFORMING TOSimilar to a call in SVr4 (but not POSIX.1).
SEE ALSOgprof(1), setitimer(2), signal(2), sigaction(2)