Name
profil — execution time profile
Synopsis
#include <unistd.h>
int
profil( |
u_short * |
buf, |
|
size_t |
bufsiz, |
|
size_t |
offset, |
|
u_int |
scale) ; |
DESCRIPTION
This 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 VALUE
Zero is always returned.
BUGS
profil
() cannot be used on a
program that also uses ITIMER_PROF
itimers.
True kernel profiling provides more accurate results. Libc
4.4 contained a kernel patch providing a system call
profil.
CONFORMING TO
Similar to a call in SVr4 (but not POSIX.1-2001).
SEE ALSO
gprof(1), setitimer(2), sigaction(2), signal(2)
Copyright 1993 Rickard E. Faith (faith@cs.unc.edu)
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Modified Fri Jun 23 01:35:19 1995 Andries Brouwer <aeb@cwi.nl>
(prompted by Bas V. de Bakker <bas@phys.uva.nl>)
Corrected (and moved to man3), 980612, aeb
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