byobu(1) byobu byobu(1)
NAME
byobu - wrapper script for seeding a user's byobu configuration and launching screen
SYNOPSIS
byobu [screen options]
Options to byobu are simply passed through screen(1).
DESCRIPTION
byobu is a script that launches GNU screen in the byobu configuration. This enables the display of system information and status notifica-
tions within two lines at the bottom of the screen session. It also enables multiple tabbed terminal sessions, accessible through simple
keystrokes.
Note that BYOBU_CONFIG_DIR=$XDG_CONFIG_HOME/byobu if defined, and $HOME/.byobu otherwise.
STATUS NOTIFICATIONS
byobu supports a number of unique and interesting status notifications across the lowest two lines in the screen. Each status notification
item is independently configurable, enabled and disabled by the configuration utility. The guide below helps identify each status item (in
alphabetical order):
apport - symbol displayed if there are pending crash reports; {!} symbol displayed on the lower bar toward the left, in black on an orange
background
arch - system architecture; displayed on the lower bar toward the left, in the default text color on the default background color
battery - battery information; display on the lower bar toward the right; |-| indicates discharging, |+| indicates charging, |=| indicates
fully charged; when charging or discharging, the current battery capacity as a percentage is displayed; the colours green, yellow, and
red are used to give further indication of the battery's charge state; you may override the detected battery by setting BAT-
TERY=/proc/acpi/battery/BAT0 in $BYOBU_CONFIG_DIR/statusrc
cpu_count - the number of cpu's or cores on the system; displayed in the lower bar toward the right in the default text color on the
default background, followed by a trailing 'x'
cpu_freq - the current frequency of the cpu in GHz; displayed in the lower bar toward the right in white text on a light blue background
cpu_temp - the cpu temperature in Celsius (default) or Fahrenheit, configure TEMP=F or TEMP=C in $BYOBU_CONFIG_DIR/statusrc; displayed in
the lower bar toward the right in yellow text on a black background; you may override the detected cpu temperature device by setting MONI-
TORED_TEMP=/proc/acpi/whatever in $BYOBU_CONFIG_DIR/statusrc
custom - user defined custom scripts; must be executable programs of any kind in $BYOBU_CONFIG_DIR/bin; must be named N_NAME, where N is
the frequency in seconds to refresh the status indicator, and NAME is the name of the script; N should not be less than 5 seconds; the
script should echo a small amount of text to standard out, standard error is discarded; the indicator will be displayed in the lower panel,
in inverted colors to your current background/foreground scheme, unless you manually specify the colors in your script's output; BEWARE,
cpu-intensive custom scripts may impact your overall system performance and could upset your system administrator!
Example: $BYOBU_CONFIG_DIR/bin/1000_uname
#!/bin/sh
printf " 05{= bw}%s 05{-}" "$(uname -r)"
date - the system date in YYYY-MM-DD formate; displayed in the lower on the far right in the default text color on the default background
disk - total disk space available and total used on / directory; displayed in the lower bar on the far right in white text on a light pur-
ple background; override the default directory by specifying an alternate mount point with MONITORED_DISK=/wherever in $BYOBU_CON-
FIG_DIR/statusrc
disk_io - instantaneous read/write througput in kB/s or MB/s over the last 3 seconds; displayed in the lower bar toward the right in white
text on a light purple background with a leading '<' sign indicating 'read speed' and '>' sign indicating 'write speed'; override the
default monitored disk by specifying an alternate device with MONITORED_DISK=/dev/sdb, and override the default DISK_IO_THRESHOLD=50 (kB/s)
in $BYOBU_CONFIG_DIR/statusrc
ec2_cost - an estimation of the cost of the current boot of the system in terms of the Amazon EC2 billing model; displayed in the lower bar
toward the right in green text on a black background; there is a leading '~' to indicate that this is an estimation, and the monetary units
are US Dollars '$'
raid - note very prominently if there is a RAID failure detected, in red blinking text on a white background; the term 'RAID' notes that
there is something wrong with the RAID, and if there is a rebuild/resync in progress, the percent complete is also shown
rcs_cost - an estimation of the cost of the current boot of the system in terms of the Rackspace Cloud Server billing model; displayed in
the lower bar toward the right in green text on a black background; there is a leading '~' to indicate that this is an estimation, and the
monetary units are US Dollars '$'
fan_speed - cpu or system fan speed as reported by lm-sensors; displayed in the lower bar toward the right in black text on a grey back-
ground; there is a trailing 'rpm' for units; you may override the detected fan by setting FAN=/sys/path/to/your/fan1_input in $BYOBU_CON-
FIG_DIR/statusrc
hostname - the hostname of the system; displayed in the upper bar on the far right in bold black text on a grey background; there is a
leading '@' symbol if the username status is also enabled
ip_address - the IPv4 address of the system in dotted decimal form; displayed in the upper bar on the far right in bold black text on a
grey background; you can override and display your IPv6 address by setting 'IPV6=1' in $BYOBU_CONFIG_DIR/statusrc
load_average - the system load average over the last 1 minute; displayed in the lower bar toward the right in black text on a yellow back-
ground
logo - an approximation of the current operating system's logo; displayed in the lower bar on the far left; you may customize this logo by
setting a chosen logo in $BYOBU_CONFIG_DIR/logo, or you may override this with LOGO=:-D in $BYOBU_CONFIG_DIR/statusrc
mail - system mail for the current user; the letter '[M]' is displayed in the lower bar toward the left in black text on a grey background
memory - total memory available and used in the system; displayed in the lower bar toward the right in white text on a green background
menu - a simple indicator directing new users to use the F9 keybinding to access the byobu menu
network - instantaneous upload/download bandwidth in [GMk]bps over the last 3 seconds; nothing is displayed if traffic is 0; displayed in
the lower bar toward the left in white text on a purple background with a leading '^' sign indicating 'up' and 'v' sign indicating 'down';
override the default interface by specifying an alternate interface with MONITORED_NETWORK=eth1, and override the default units (bits) with
NETWORK_UNITS=bytes, and override the default NETWORK_THRESHOLD=20 (kbps) in $BYOBU_CONFIG_DIR/statusrc
notify_osd - Send on-screen notification messages to screen's notification buffer
processes - total number of processes running on the system; displayed in the lower bar in white text on a dark yellow background with a
trailing '&' indicating 'background processes'
reboot_required - symbol present if a reboot is required following a system update; displayed in the lower bar white text on a blue back-
ground by the symbol '(R)'; additionally, reboot_required will print '<F5>' in white text on a blue background, if Byobu requires you to
reload your profile to affect some changes; it will also detect if your system is currently in powernap(8) state and if so print '.zZ'.
release - distribution and version information about the release running on the current system as reported by lsb_release(1) or /etc/issue;
displayed in the lower bar in bold black text toward the left on a grey background; you may override the detected release with DISTRO=What-
ever in $BYOBU_CONFIG_DIR/statusrc
services - users can configure a list of services to monitor, define the SERVICES variable in $BYOBU_CONFIG_DIR/statusrc, a whitespace sep-
arated of services, each service should include the init name of the service, then a pipe, and then an abbreviated name or symbol to dis-
play when running (e.g. SERVICES="ssh|ssh apache2|http"); displayed in the lower bar toward the center in cyan on a white background
swap - total swap space and total used as a percentage of the total available; displayed in the lower bar toward the right in white text on
a light green background with a trailing '%' sign
time - the system time in HH:MM:SS format; displayed in the lower bar on the far right in the default text and default background colors
time_binary - only for the hard core geek, the local system time in binary; requires UTF8 support in a VERY recent version of GNU Screen;
you must additionally set "UTF8=1" in $BYOBU_CONFIG_DIR/statusrc; displayed in the lower bar on the far right in the default text and back-
ground colors
time_utc - the UTC system time in HH:MMformat; displayed in the lower bar on the far right in dark text on a light background
updates_available - the number of updates available on the system; displayed in the lower bar toward the right in white text on a red back-
ground with a trailing '!' sign; if any updates are marked 'security updates', then there will be a total of two trailing exclamation
points, '!!'
uptime - the total system uptime since last boot; displayed in the lower bar toward the right in blue text on a grey background
users - the number of remote users logged into the system via sshd, empty if 0 users; displayed in the lower bar toward the right in red
text on a grey background with a trailing '#' sign
whoami - the name of the user who owns the screen session; displayed in the upper bar toward the far right in bold black text on a grey
background
wifi_quality - the connection rate and signal quality of the wifi connection; displayed in the lower bar toward the right in black text on
a cyan background; the connection rate is in 'Mb/s' and the signal quality is as a percentage with a trailing '%'; override the default
interface by specifying an alternate interface with MONITORED_NETWORK=wlan0 in $BYOBU_CONFIG_DIR/statusrc
SESSIONS
Byobu name screen sessions "byobu", if unspecified. To hide sessions from byobu-select-session(1), prepend a "." to the beginning of the
session name, like:
byobu -S .hidden
WINDOWS
Each open window in the screen session is displayed in the upper bar toward the far left. These are numbered, and include indicators as to
activity in the window (see "activity" in screen(1) for symbol definitions). The current active window is highlighted by inverting the
background/text from the rest of the window bar.
Users can create a list of windows to launch at startup in $BYOBU_CONFIG_DIR/windows. This file is the same syntax as ~/.screenrc, each
line specifying a window using the "screen" command, as described in screen(1).
User can also launch Byobu with unique window sets. Users can store these as $BYOBU_CONFIG_DIR/windows.[NAME], and launch Byobu with the
environment variable BYOBU_WINDOWS.
For example:
$ cat $BYOBU_CONFIG_DIR/windows.ssh_sessions
screen -t localhost bash
screen -t aussie ssh root@aussie
screen -t beagle ssh root@beagle
screen -t collie ssh root@collie
$ BYOBU_WINDOWS=ssh_sessions byobu
UNITS OF MEASURE
byobu uses binary for capacity measurements of KB, MB, GB, and TB. This means multiples of 1024 rather than multiples of 1000, in accor-
dance with JEDEC Standard 100B.01 for disk and memory capacity measurements. See:
* http://en.wikipedia.org/wiki/JEDEC_memory_standards
byobu uses decimal for measurements of network data transfer, meaning multiple of 1000, rather than 1024. See:
* http://en.wikipedia.org/wiki/Data_rate_units
KEYBINDINGS
byobu keybindings can be user defined in /usr/share/byobu/keybindings/ (or within .screenrc if byobu-export was used). The common key bind-
ings are:
F2 - Create a new window
F3 - Move to previous window
F4 - Move to next window
F5 - Reload profile
F6 - Detach from this session
F7 - Enter copy/scrollback mode
F8 - Re-title a window
F9 - Configuration Menu
F12 - Lock this terminal
shift-F2 - Split the screen horizontally
ctrl-F2 - Split the screen vertically
shift-F3 - Shift the focus to the previous split region
shift-F4 - Shift the focus to the next split region
shift-F5 - Join all splits
ctrl-F6 - Remove this split
ctrl-F5 - Reconnect GPG and SSH sockets
shift-F6 - Detach, but do not logout
alt-pgup - Enter scrollback mode
alt-pgdn - Enter scrollback mode
Ctrl-a $ - show detailed status
Ctrl-a R - Reload profile
Ctrl-a ! - Toggle key bindings on and off
Ctrl-a k - Kill the current window
Ctrl-a ~ - Save the current window's scrollback buffer
BUGS
For Byobu colors to work properly, older versions of GNU Screen require a 1-line patch to adjust MAX_WINMSG_REND in screen.c. The change
is in GNU Screen's upstream source control system as of 2010-01-26, but GNU Screen has not released a new upstream version in several
years. You can disable colors entirely by setting MONOCHROME=1 in $BYOBU_CONFIG_DIR/statusrc. For more information, see:
* http://savannah.gnu.org/bugs/?22146
PuTTY users have reported that the F2, F3, and F4 shortcut keys are not working properly. PuTTY sends the same escape sequences as the
linux console for F1-F4 by default. You can fix this problem in the PuTTY config, Terminal -> Keyboard -> Function keys: Xterm R6. See:
http://www.mail-archive.com/screen-users@gnu.org/msg01525.html
Apple Mac OSX terminal users have reported 'flashing text'. You can fix this in the advanced settings of the terminal application, with
'Declare Terminal As: xterm-color'.
Apple Mac keyboard users may need to specify a vt100 terminal by adding this to your OSX profile, in order to get Byobu's function keys and
colors to work:
alias ssh='TERM=vt100 ssh'
Users of a non-UTF8 locale (such as cs_CZ charset ISO-8859-2), may need to add "defutf8 off" to ~/.screenrc, if some characters are render-
ing as "?".
Users who customize their PS1 prompt need to put this setting in ~/.bashrc, rather than ~/.profile, in order for it to work correctly with
Byobu.
If you run byobu(1) under sudo(8), you must use the -H option, such that the user's $HOME directory environment variable is set properly.
Otherwise, byobu(1) will create a bunch of directories in the $SUDO_USER's $HOME, but will be owned by root. To prevent this from happen-
ing, byobu(1) will simply refuse to run if $USER does not own $HOME.
SEE ALSO
screen(1), byobu-config(1), byobu-export(1), byobu-status(1), byobu-status-detail(1), byobu-enable(1), byobu-launch(1)
http://launchpad.net/byobu
AUTHOR
This manpage and the utility were written by Dustin Kirkland <kirkland@ubuntu.com> for Ubuntu systems (but may be used by others). Permis-
sion is granted to copy, distribute and/or modify this document and the utility under the terms of the GNU General Public License, Version
3 published by the Free Software Foundation.
The complete text of the GNU General Public License can be found in /usr/share/common-licenses/GPL on Debian/Ubuntu systems, or in
/usr/share/doc/fedora-release-*/GPL on Fedora systems, or on the web at http://www.gnu.org/licenses/gpl.txt.
byobu 19 June 2009 byobu(1)