diff options
Diffstat (limited to 'man2/bdflush.2')
| -rw-r--r-- | man2/bdflush.2 | 110 |
1 files changed, 110 insertions, 0 deletions
diff --git a/man2/bdflush.2 b/man2/bdflush.2 new file mode 100644 index 000000000..5a04862c0 --- /dev/null +++ b/man2/bdflush.2 @@ -0,0 +1,110 @@ +.\" Hey Emacs! This file is -*- nroff -*- source. +.\" +.\" Copyright (c) 1995 Michael Chastain (mec@shell.portal.com), 15 April 1995. +.\" +.\" This is free documentation; you can redistribute it and/or +.\" modify it under the terms of the GNU General Public License as +.\" published by the Free Software Foundation; either version 2 of +.\" the License, or (at your option) any later version. +.\" +.\" The GNU General Public License's references to "object code" +.\" and "executables" are to be interpreted as the output of any +.\" document formatting or typesetting system, including +.\" intermediate and printed output. +.\" +.\" This manual is distributed in the hope that it will be useful, +.\" but WITHOUT ANY WARRANTY; without even the implied warranty of +.\" MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +.\" GNU General Public License for more details. +.\" +.\" You should have received a copy of the GNU General Public +.\" License along with this manual; if not, write to the Free +.\" Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111, +.\" USA. +.\" +.\" Modified 1997-01-31 by Eric S. Raymond <esr@thyrsus.com> +.\" Modified 2004-06-17 by Michael Kerrisk <mtk16@ext.canterbury.ac.nz> +.\" +.TH BDFLUSH 2 2004-06-17 "Linux 2.6.7" "Linux Programmer's Manual" +.SH NAME +bdflush \- start, flush, or tune buffer-dirty-flush daemon +.SH SYNOPSIS +.nf +.BI "int bdflush(int " func ", long *" address ); +.BI "int bdflush(int " func ", long " data ); +.fi +.SH DESCRIPTION +.B bdflush +starts, flushes, or tunes the buffer-dirty-flush daemon. +Only a privileged process (one with the +.B CAP_SYS_ADMIN +capability) may call +.BR bdflush . +.PP +If +.I func +is negative or 0, and no daemon has been started, then +.B bdflush +enters the daemon code and never returns. +.PP +If +.I func +is 1, +some dirty buffers are written to disk. +.PP +If +.I func +is 2 or more and is even (low bit is 0), then +.I address +is the address of a long word, +and the tuning parameter numbered +.RI "(" "func" "\-2)/2" +is returned to the caller in that address. +.PP +If +.I func +is 3 or more and is odd (low bit is 1), then +.I data +is a long word, +and the kernel sets tuning parameter numbered +.RI "(" "func" "\-3)/2" +to that value. +.PP +The set of parameters, their values, and their legal ranges +are defined in the kernel source file +.IR fs/buffer.c . +.SH "RETURN VALUE" +If +.I func +is negative or 0 and the daemon successfully starts, +.B bdflush +never returns. +Otherwise, the return value is 0 on success and \-1 on failure, with +.I errno +set to indicate the error. +.SH ERRORS +.TP +.B EBUSY +An attempt was made to enter the daemon code after +another process has already entered. +.TP +.B EFAULT +.I address +points outside your accessible address space. +.TP +.B EINVAL +An attempt was made to read or write an invalid parameter number, +or to write an invalid value to a parameter. +.TP +.B EPERM +Caller does not have the +.B CAP_SYS_ADMIN +capability. +.SH "CONFORMING TO" +\fBbdflush\fP is Linux specific and should not be used in programs +intended to be portable. +.SH "SEE ALSO" +.BR fsync (2), +.BR sync (2), +.BR sync (8), +.BR update (8) |