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diff --git a/man3/ffs.3 b/man3/ffs.3 new file mode 100644 index 000000000..12aaef1b0 --- /dev/null +++ b/man3/ffs.3 @@ -0,0 +1,63 @@ +.\" Copyright 1993 David Metcalfe (david@prism.demon.co.uk) +.\" +.\" 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 +.\" +.\" Since the Linux kernel and libraries are constantly changing, this +.\" manual page may be incorrect or out-of-date.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. +.\" +.\" References consulted: +.\" Linux libc source code +.\" Lewine's _POSIX Programmer's Guide_ (O'Reilly & Associates, 1991) +.\" 386BSD man pages +.\" Modified Sat Jul 24 19:39:35 1993 by Rik Faith (faith@cs.unc.edu) +.\" +.\" Modified 2003 Walter Harms (walter.harms@informatik.uni-oldenburg.de) +.\" +.TH FFS 3 2003-08-05 "GNU" "Linux Programmer's Manual" +.SH NAME +ffs \- find first bit set in a word +.SH SYNOPSIS +.nf +.B #include <strings.h> +.sp +.BI "int ffs(int " i ); +.sp +.B #define _GNU_SOURCE +.br +.B #include <string.h> +.sp +.BI "int ffsl(long int " i ); +.sp +.BI "int ffsll(long long int " i ); +.fi +.SH DESCRIPTION +The \fBffs()\fP function returns the position of the first +(least significant) bit set in the word \fIi\fP. +The least significant bit is position 1 and the +most significant position e.g. 32 or 64. +.BR +The functions \fBffsll()\fP and \fBffsl()\fP do the same but take +arguments of possibly different size. +.SH "RETURN VALUE" +These functions return the position of the first bit set, +or 0 if no bits are set. +.SH "CONFORMING TO" +BSD 4.3, POSIX 1003.1-2001. +.SH NOTES +BSD systems have a prototype in +.IR <string.h> . |