PROFIL
Section: Linux Programmer's Manual (3)
Updated: 2007-07-26
Index
Return to Main Contents
NAME
profil - execution time profile
SYNOPSIS
#include <unistd.h>
int profil(unsigned short *buf, size_t bufsiz, size_t offset, unsigned int scale);
Feature Test Macro Requirements for glibc (see
feature_test_macros(7)):
profil():
_BSD_SOURCE || (_XOPEN_SOURCE && _XOPEN_SOURCE < 500)
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.
CONFORMING TO
Similar to a call in SVr4 (but not POSIX.1-2001).
BUGS
profil()
cannot be used on a program that also uses
ITIMER_PROF
interval timers (see
setitimer(2)).
True kernel profiling provides more accurate results.
Libc 4.4 contained a kernel patch providing a system call profil.
SEE ALSO
gprof(1),
setitimer(2),
sigaction(2),
signal(2)
COLOPHON
This page is part of release 3.27 of the Linux
man-pages
project.
A description of the project,
and information about reporting bugs,
can be found at
http://www.kernel.org/doc/man-pages/.
Index
- NAME
-
- SYNOPSIS
-
- DESCRIPTION
-
- RETURN VALUE
-
- CONFORMING TO
-
- BUGS
-
- SEE ALSO
-
- COLOPHON
-
This document was created by
man2html,
using the manual pages.
Time: 19:49:24 GMT, April 27, 2011