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NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | ATTRIBUTES | CONFORMING TO | BUGS | SEE ALSO | COLOPHON |
PROFIL(3) Linux Programmer's Manual PROFIL(3)
profil - execution time profile
#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():
Since glibc 2.21:
_DEFAULT_SOURCE
In glibc 2.19 and 2.20:
_DEFAULT_SOURCE || (_XOPEN_SOURCE && _XOPEN_SOURCE < 500)
Up to and including glibc 2.19:
_BSD_SOURCE || (_XOPEN_SOURCE && _XOPEN_SOURCE < 500)
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.
Zero is always returned.
For an explanation of the terms used in this section, see
attributes(7).
┌──────────┬───────────────┬───────────┐
│Interface │ Attribute │ Value │
├──────────┼───────────────┼───────────┤
│profil() │ Thread safety │ MT-Unsafe │
└──────────┴───────────────┴───────────┘
Similar to a call in SVr4 (but not POSIX.1).
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.
gprof(1), sprof(1), setitimer(2), sigaction(2), signal(2)
This page is part of release 4.12 of the Linux man-pages project. A
description of the project, information about reporting bugs, and the
latest version of this page, can be found at
https://www.kernel.org/doc/man-pages/.
Linux 2016-03-15 PROFIL(3)
Pages that refer to this page: syscalls(2), unimplemented(2)