dmesg \- print or control the kernel ring buffer
.SH SYNOPSIS
.B dmesg
-.RB [ options ]
+[options]
.sp
-dmesg \-\-clear
+.B dmesg \-\-clear
.br
-dmesg \-\-read-clear [options]
+.BR "dmesg \-\-read-clear " [options]
.br
-dmesg \-\-console-level level
+.BI "dmesg \-\-console-level " level
.br
-dmesg \-\-console-on
+.B dmesg \-\-console-on
.br
-dmesg \-\-console-off
+.B dmesg \-\-console-off
.SH DESCRIPTION
.B dmesg
is used to examine or control the kernel ring buffer.
.PP
The default action is to read all messages from the kernel ring buffer.
.SH OPTIONS
-The \-\-clear, \-\-read-clear, \-\-console-on, \-\-console-off and
-\-\-console-level options are mutually exclusive.
+The
+.BR \-\-clear ,
+.BR \-\-read-clear ,
+.BR \-\-console-on ,
+.BR \-\-console-off ,
+and
+.B \-\-console-level
+options are mutually exclusive.
.PP
.IP "\fB\-C\fR, \fB\-\-clear\fR"
Clear the ring buffer.
.IP "\fB\-c\fR, \fB\-\-read-clear\fR"
Clear the ring buffer after first printing its contents.
.IP "\fB\-D\fR, \fB\-\-console-off\fR"
-Disable printing messages to the console.
+Disable the printing of messages to the console.
.IP "\fB\-d\fR, \fB\-\-show-delta\fR"
Display the timestamp and the time delta spent between messages. If used
together with
.B \-\-notime
then only the time delta without the timestamp is printed.
-.IP "\fB\-e\fR, \fB\-\-reltime\fR"
-Display the local time and the delta in human-readable format.
.IP "\fB\-E\fR, \fB\-\-console-on\fR"
Enable printing messages to the console.
+.IP "\fB\-e\fR, \fB\-\-reltime\fR"
+Display the local time and the delta in human-readable format.
.IP "\fB\-F\fR, \fB\-\-file \fIfile\fR"
Read the messages from the given
.IR file .
of facilities. For example:
.PP
.RS 14
-dmesg \-\-facility=daemon
+.B dmesg \-\-facility=daemon
.RE
.IP
will print messages from system daemons only. For all supported facilities
-see
-.B dmesg \-\-help
+see the
+.B \-\-help
output.
.IP "\fB\-H\fR, \fB\-\-human\fR"
Enable human-readable output. See also \fB\-\-color\fR, \fB\-\-reltime\fR
.IP "\fB\-L\fR, \fB\-\-color\fR[=\fIwhen\fR]"
Colorize important messages (enabled by default). The optional argument \fIwhen\fP
can be \fBauto\fR, \fBnever\fR or \fBalways\fR. If the \fIwhen\fR argument is omitted,
-then it defaults to \fBauto\fR.
+it defaults to \fBauto\fR.
.IP "\fB\-l\fR, \fB\-\-level \fIlist\fR"
Restrict output to the given (comma-separated)
.I list
of levels. For example:
.PP
.RS 14
-dmesg \-\-level=err,warn
+.B dmesg \-\-level=err,warn
.RE
.IP
-will print error and warning messages only. For all supported levels see
-.B dmesg \-\-help
+will print error and warning messages only. For all supported levels see the
+.B \-\-help
output.
.IP "\fB\-n\fR, \fB\-\-console-level \fIlevel\fR
Set the
at which printing of messages is done to the console. The
.I level
is a level number or abbreviation of the level name. For all supported
-levels see
-.B dmesg \-\-help
+levels see the
+.B \-\-help
output.
.sp
For example,
the time may be inaccurate when a system is suspended and resumed.
.SH COLORS
Implicit coloring can be disabled by an empty file \fI/etc/terminal-colors.d/dmesg.disable\fR.
-
See
.BR terminal-colors.d (5)
-for more details about colorization configuration. The logical color names
-support by
+for more details about colorization configuration.
+.PP
+The logical color names supported by
.B dmesg
are:
.TP
eject \- eject removable media
.SH SYNOPSIS
.B eject
-.RB [ options ]
+[options]
.IR device | mountpoint
.SH DESCRIPTION
-.B Eject
+.B eject
allows removable media (typically a CD-ROM, floppy disk, tape, JAZ, ZIP or USB
disk) to be ejected under software control. The command can also control some
multi-disc CD-ROM changers, the auto-eject feature supported by some devices,
and close the disc tray of some CD-ROM drives.
.PP
The device corresponding to \fIdevice\fP or \fImountpoint\fP is ejected. If no
-name is specified, the default name /dev/cdrom is used. The device may be
+name is specified, the default name \fB/dev/cdrom\fR is used. The device may be
addressed by device name (e.g. 'sda'), device path (e.g. '/dev/sda'),
-UUID=<uuid> or LABEL=<label> tags.
+UUID=\fIuuid\fR or LABEL=\fIlabel\fR tags.
.PP
There are four different methods of ejecting, depending on whether the device
-is a CD-ROM, SCSI device, removable floppy, or tape. By default eject tries
+is a CD-ROM, SCSI device, removable floppy, or tape. By default \fBeject\fR tries
all four methods in order until it succeeds.
.PP
-If device partition is specified, the whole-disk device is used. If the device
+If a device partition is specified, the whole-disk device is used. If the device
or a device partition is currently mounted, it is unmounted before ejecting.
.SH OPTIONS
-.IP "\fB\-a, \-\-auto \fIon|off\fP"
+.IP "\fB\-a\fR, \fB\-\-auto on\fR|\fBoff\fR"
This option controls the auto-eject mode, supported by some devices. When
enabled, the drive automatically ejects when the device is closed.
.IP "\fB\-c, \-\-changerslot \fIslot\fP"
With this option a CD slot can be selected from an ATAPI/IDE CD-ROM changer.
-Linux 2.0 or higher is required to use this feature. The CD-ROM drive can not
+Linux 2.0 or higher is required to use this feature. The CD-ROM drive cannot
be in use (mounted data CD or playing a music CD) for a change request to work.
Please also note that the first slot of the changer is referred to as 0, not 1.
.IP "\fB\-d, \-\-default\fP"
Force eject, don't check device type.
.IP "\fB\-h, \-\-help\fP"
Display help text and exit.
-.IP "\fB\-i, \-\-manualeject \fIon|off\fP"
+.IP "\fB\-i\fR, \fB\-\-manualeject on\fR|\fBoff\fR"
This option controls locking of the hardware eject button. When enabled, the
drive will not be ejected when the button is pressed. This is useful when you
are carrying a laptop in a bag or case and don't want it to eject if the button
is inadvertently pressed.
.IP "\fB\-p, \-\-proc\fP"
-This option allow you to use /proc/mounts instead /etc/mtab. It also passes the
-\-n option to \fBumount\fR(1).
+This option allows you to use /proc/mounts instead /etc/mtab. It also passes the
+\fB\-n\fR option to \fBumount\fR(1).
.IP "\fB\-q, \-\-tape\fP"
This option specifies that the drive should be ejected using a tape drive
offline command.
.IP "\fB\-m, \-\-no-unmount\fP"
The option tells eject to not try to unmount at all.
.IP "\fB\-M, \-\-no-partitions-unmount\fP"
-The option tells eject to not try to unmount another partitions on partitioned
-devices. If another partition is mounted the program will not attempt to eject
-the media. It will attempt to unmount only mountpoint or mounted device given
-on eject command line.
+The option tells eject to not try to unmount other partitions on partitioned
+devices. If another partition is still mounted, the program will not attempt
+to eject the media. It will attempt to unmount only the device or mountpoint
+given on the command line.
.IP "\fB\-n, \-\-noop\fP"
With this option the selected device is displayed but no action is performed.
.IP "\fB\-t, \-\-trayclose\fP"
doing.
.IP "\fB\-V, \-\-version\fP"
Display version information and exit.
-.IP "\fB\-x, \-\-cdspeed \fI<speed>\fP"
-With this option the drive is given a CD-ROM select speed command. The speed
+.IP "\fB\-x, \-\-cdspeed \fIspeed\fP"
+With this option the drive is given a CD-ROM select speed command. The
+.I speed
argument is a number indicating the desired speed (e.g. 8 for 8X speed), or 0
for maximum data rate. Not all devices support this command and you can only
specify speeds that the drive is capable of. Every time the media is changed
-this option is cleared. This option can be used alone, or with the \-t and \-c
-options.
+this option is cleared. This option can be used alone, or with the
+\fB\-t\fR and \fB\-c\fR options.
.IP "\fB\-X, \-\-listspeed\fP"
With this option the CD-ROM drive will be probed to detect the available
speeds. The output is a list of speeds which can be used as an argument of the
-\-x option. This only works with Linux 2.6.13 or higher, on previous versions
-solely the maximum speed will be reported. Also note that some drive may not
+\fB\-x\fR option. This only works with Linux 2.6.13 or higher, on previous versions
+solely the maximum speed will be reported. Also note that some drives may not
correctly report the speed and therefore this option does not work with them.
.SH EXIT STATUS
Returns 0 if operation was successful, 1 if operation failed or command syntax
was not valid.
.SH NOTES
-.B Eject
+.B eject
only works with devices that support one or more of the four methods of
ejecting. This includes most CD-ROM drives (IDE, SCSI, and proprietary), some
SCSI tape drives, JAZ drives, ZIP drives (parallel port, SCSI, and IDE
.B eject
program itself.
.PP
-The \-r, \-s, \-f, and \-q options allow controlling which methods are used to
+The \fB\-r\fR, \fB\-s\fR, \fB\-f\fR, and \fB\-q\fR options allow controlling
+which methods are used to
eject. More than one method can be specified. If none of these options are
specified, it tries all four (this works fine in most cases).
.PP
-.B Eject
+.B eject
may not always be able to determine if the device is mounted (e.g. if it has
several names). If the device name is a symbolic link,
.B eject
If
.B eject
determines that the device can have multiple partitions, it will attempt to
-unmount all mounted partitions of the device before ejecting (see
---no-partitions-unmount). If an unmount fails, the program will not attempt to
-eject the media.
+unmount all mounted partitions of the device before ejecting (see also
+\fB--no-partitions-unmount\fR). If an unmount fails, the program will not
+attempt to eject the media.
.PP
You can eject an audio CD. Some CD-ROM drives will refuse to open the tray if
the drive is empty. Some devices do not support the tray close command.
.\" OTHER DEALINGS IN THE SOFTWARE.
.\"
.\" -----------------------------------------------------------------------
-.TH FLOCK 1 "September 2011" "util-linux" "User Commands"
+.TH FLOCK 1 "July 2014" "util-linux" "User Commands"
.SH NAME
flock \- manage locks from shell scripts
.SH SYNOPSIS
.B flock
-[options] <file|directory> <command> [command args]
+[options]
+.IR file | "directory command " [ arguments ]
.br
.B flock
-[options] <file|directory> -c <command>
+[options]
+.IR file | directory
+.BI \-c " command"
.br
.B flock
-[options] <file descriptor number>
+.RI [options] " number"
.SH DESCRIPTION
.PP
This utility manages
.BR flock (2)
-locks from within shell scripts or the command line.
+locks from within shell scripts or from the command line.
.PP
-The first and second forms wrap the lock around the executing a command, in
-a manner similar to
+The first and second of the above forms wrap the lock around the execution of a
+.IR command ,
+in a manner similar to
.BR su (1)
or
.BR newgrp (1).
-It locks a specified file or directory, which is created (assuming
-appropriate permissions), if it does not already exist. By default, if the
+They lock a specified \fIfile\fR or \fIdirectory\fR, which is created (assuming
+appropriate permissions) if it does not already exist. By default, if the
lock cannot be immediately acquired,
.B flock
waits until the lock is available.
.PP
-The third form uses open file by file descriptor number. See examples how
-that can be used.
+The third form uses an open file by its file descriptor \fInumber\fR.
+See the examples below for how that can be used.
.SH OPTIONS
.TP
\fB\-s\fP, \fB\-\-shared\fP
Fail rather than wait if the lock cannot be
immediately acquired.
See the
-.I \-E
+.B \-E
option for the exit code used.
.TP
\fB\-w\fP, \fB\-\-wait\fP, \fB\-\-timeout\fP \fIseconds\fP
.IR seconds .
Decimal fractional values are allowed.
See the
-.I \-E
+.B \-E
option for the exit code used.
.TP
\fB\-o\fP, \fB\-\-close\fP
Close the file descriptor on which the lock is held before executing
-.BR command\ .
+.IR command .
This is useful if
-.B command
+.I command
spawns a child process which should not be holding the lock.
.TP
\fB\-E\fP, \fB\-\-conflict\-exit\-code\fP \fInumber\fP
The exit code used when the \fB\-n\fP option is in use, and the
conflicting lock exists, or the \fB\-w\fP option is in use,
-and the timeout is reached. The default value is 1.
+and the timeout is reached. The default value is 1.
.TP
\fB\-c\fP, \fB\-\-command\fP \fIcommand\fP
Pass a single
The command uses
.B sysexits.h
return values for everything, except when using either of the options
-.I \-n
+.B \-n
or
-.I \-w
+.B \-w
which report a failure to acquire the lock with a return value given by the
-.I \-E
+.B \-E
option, or 1 by default.
.PP
-When using the <command> variant, and executing the child worked, then
+When using the \fIcommand\fR variant, and executing the child worked, then
the exit status is that of the child command.
.SH AUTHOR
.UR hpa@zytor.com
projects / thirdparty / util-linux.git / commitdiff
