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diff --git a/man3/profil.3 b/man3/profil.3 new file mode 100644 index 000000000..b7a6425b5 --- /dev/null +++ b/man3/profil.3 @@ -0,0 +1,71 @@ +.\" Hey Emacs! This file is -*- nroff -*- source. +.\" +.\" Copyright 1993 Rickard E. Faith (faith@cs.unc.edu) +.\" +.\" Permission is granted to make and distribute verbatim copies of this +.\" manual provided the copyright notice and this permission notice are +.\" preserved on all copies. +.\" +.\" Permission is granted to copy and distribute modified versions of this +.\" manual under the conditions for verbatim copying, provided that the +.\" entire resulting derived work is distributed under the terms of a +.\" permission notice identical to this one. +.\" +.\" Since the Linux kernel and libraries are constantly changing, this +.\" manual page may be incorrect or out-of-date. The author(s) assume no +.\" responsibility for errors or omissions, or for damages resulting from +.\" the use of the information contained herein. The author(s) may not +.\" have taken the same level of care in the production of this manual, +.\" which is licensed free of charge, as they might when working +.\" professionally. +.\" +.\" Formatted or processed versions of this manual, if unaccompanied by +.\" the source, must acknowledge the copyright and authors of this work. +.\" +.\" 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 +.TH PROFIL 3 1993-07-23 "Linux 2.0" "Linux Programmer's Manual" +.SH NAME +profil \- execution time profile +.SH SYNOPSIS +.B #include <unistd.h> +.sp +.BI "int profil(u_short *" buf ", size_t " bufsiz ", size_t " offset ", u_int " scale ); +.SH DESCRIPTION +This routine provides a means to find out in what areas your program +spends most of its time. The argument +.I buf +points to +.I bufsiz +bytes of core. Every virtual 10 milliseconds, the user's program counter (PC) +is examined: +.I offset +is subtracted and the result is multiplied by +.IR scale +and divided by 65536. +If the resulting value is less than +.IR bufsiz , +then the corresponding entry in +.I buf +is incremented. +If +.I buf +is NULL, profiling is disabled. +.SH "RETURN VALUE" +Zero is always returned. +.SH BUGS +.B profil +cannot be used on a program that also uses +.B ITIMER_PROF +itimers. + +True kernel profiling provides more accurate results. +Libc 4.4 contained a kernel patch providing a system call profil. +.SH "CONFORMING TO" +Similar to a call in SVr4 (but not POSIX.1). +.SH "SEE ALSO" +.BR gprof (1), +.BR setitimer (2), +.BR sigaction (2), +.BR signal (2) |