fix wrong memory-documentation

[i3/i3status] / man / i3status.man

i3status(1)
===========
Michael Stapelberg <michael@i3wm.org>
v2.11, January 2017

== NAME

i3status - Generates a status line for i3bar, dzen2, xmobar or lemonbar

== SYNOPSIS

i3status [-c configfile] [-h] [-v]

== OPTIONS

-c::
Specifies an alternate configuration file path. By default, i3status looks for
configuration files in the following order:

1. ~/.config/i3status/config (or $XDG_CONFIG_HOME/i3status/config if set)
2. /etc/xdg/i3status/config (or $XDG_CONFIG_DIRS/i3status/config if set)
3. ~/.i3status.conf
4. /etc/i3status.conf

== DESCRIPTION

i3status is a small program for generating a status bar for i3bar, dzen2,
xmobar, lemonbar or similar programs. It is designed to be very efficient by
issuing a very small number of system calls, as one generally wants to update
such a status line every second. This ensures that even under high load, your
status bar is updated correctly. Also, it saves a bit of energy by not hogging
your CPU as much as spawning the corresponding amount of shell commands would.

== CONFIGURATION

The basic idea of i3status is that you can specify which "modules" should
be used (the order directive). You can then configure each module with its
own section. For every module, you can specify the output format. See below
for a complete reference.

.Sample configuration
-------------------------------------------------------------
general {
        output_format = "dzen2"
        colors = true
        interval = 5
}

order += "ipv6"
order += "disk /"
order += "run_watch DHCP"
order += "run_watch VPNC"
order += "path_exists VPN"
order += "wireless wlan0"
order += "ethernet eth0"
order += "battery 0"
order += "cpu_temperature 0"
order += "memory"
order += "load"
order += "tztime local"
order += "tztime berlin"

wireless wlan0 {
        format_up = "W: (%quality at %essid, %bitrate) %ip"
        format_down = "W: down"
}

ethernet eth0 {
        # if you use %speed, i3status requires the cap_net_admin capability
        format_up = "E: %ip (%speed)"
        format_down = "E: down"
}

battery 0 {
        format = "%status %percentage %remaining %emptytime"
        format_down = "No battery"
        status_chr = "⚡ CHR"
        status_bat = "🔋 BAT"
        status_unk = "? UNK"
        status_full = "☻ FULL"
        path = "/sys/class/power_supply/BAT%d/uevent"
        low_threshold = 10
}

run_watch DHCP {
        pidfile = "/var/run/dhclient*.pid"
}

run_watch VPNC {
        # file containing the PID of a vpnc process
        pidfile = "/var/run/vpnc/pid"
}

path_exists VPN {
        # path exists when a VPN tunnel launched by nmcli/nm-applet is active
        path = "/proc/sys/net/ipv4/conf/tun0"
}

tztime local {
        format = "%Y-%m-%d %H:%M:%S"
}

tztime berlin {
        format = "%Y-%m-%d %H:%M:%S %Z"
        timezone = "Europe/Berlin"
}

load {
        format = "%5min"
}

cpu_temperature 0 {
        format = "T: %degrees °C"
        path = "/sys/devices/platform/coretemp.0/temp1_input"
}

memory {
        format = "%used"
        threshold_degraded = "10%"
        format_degraded = "MEMORY: %free"
}

disk "/" {
        format = "%free"
}
-------------------------------------------------------------

=== General

The +colors+ directive will disable all colors if you set it to +false+. You can
also specify the colors that will be used to display "good", "degraded" or "bad"
values using the +color_good+, +color_degraded+ or +color_bad+ directives,
respectively. Those directives are only used if color support is not disabled by
the +colors+ directive. The input format for color values is the canonical RGB
hexadecimal triplet (with no separators between the colors), prefixed by a hash
character ("#").

*Example configuration*:
-------------------------------------------------------------
color_good = "#00FF00"
-------------------------------------------------------------

Likewise, you can use the +color_separator+ directive to specify the color that
will be used to paint the separator bar. The separator is always output in
color, even when colors are disabled by the +colors+ directive. This option has
no effect when +output_format+ is set to +i3bar+ or +none+.

The +interval+ directive specifies the time in seconds for which i3status will
sleep before printing the next status line.

Using +output_format+ you can choose which format strings i3status should
use in its output. Currently available are:

i3bar::
i3bar comes with i3 and provides a workspace bar which does the right thing in
multi-monitor situations. It also comes with tray support and can display the
i3status output. This output type uses JSON to pass as much meta-information to
i3bar as possible (like colors, which blocks can be shortened in which way,
etc.).
dzen2::
Dzen is a general purpose messaging, notification and menuing program for X11.
It was designed to be scriptable in any language and integrate well with window
managers like dwm, wmii and xmonad though it will work with any windowmanger
xmobar::
xmobar is a minimalistic, text based, status bar. It was designed to work
with the xmonad Window Manager.
lemonbar::
lemonbar is a lightweight bar based entirely on XCB. It has full UTF-8 support
and is EWMH compliant.
term::
Use ANSI Escape sequences to produce a terminal-output as close as possible to
the graphical outputs. This makes debugging your config file a little bit
easier because the terminal-output of i3status becomes much more readable, but
should only used for such quick glances, because it will only support very
basic output-features (for example you only get 3 bits of color depth).
none::
Does not use any color codes. Separates values by the pipe symbol by default.
This should be used with i3bar and can be used for custom scripts.

It's also possible to use the color_good, color_degraded, color_bad directives
to define specific colors per module. If one of these directives is defined
in a module section its value will override the value defined in the general
section just for this module.

If you don't fancy the vertical separators between modules i3status/i3bar
uses by default, you can employ the +separator+ directive to configure how
modules are separated. You can also disable the default separator altogether by
setting it to the empty string. You might then define separation as part of a
module's format string. This is your only option when using the i3bar output
format as the separator is drawn by i3bar directly otherwise. For the other
output formats, the provided non-empty string will be automatically enclosed
with the necessary coloring bits if color support is enabled.

i3bar supports Pango markup, allowing your format strings to specify font,
color, size, etc. by setting the +markup+ directive to "pango". Note that the
ampersand ("&"), less-than ("<"), greater-than (">"), single-quote ("'"), and
double-quote (""") characters need to be replaced with "`&amp;`", "`&lt;`",
"`&gt;`", "`&apos;`", and "`&quot;`" respectively. This is done automatically
for generated content (e.g. wireless ESSID, time).

*Example configuration*:

-------------------------------------------------------------
general {
    output_format = "xmobar"
    separator = "  "
}

order += "load"
order += "disk /"

load {
    format = "[ load: %1min, %5min, %15min ]"
}
disk "/" {
    format = "%avail"
}
-------------------------------------------------------------

=== IPv6

This module gets the IPv6 address used for outgoing connections (that is, the
best available public IPv6 address on your computer).

*Example format_up*: +%ip+

*Example format_down*: +no IPv6+

=== Disk

Gets used, free, available and total amount of bytes on the given mounted filesystem.

These values can also be expressed in percentages with the percentage_used,
percentage_free, percentage_avail and percentage_used_of_avail formats.

Byte sizes are presented in a human readable format using a set of prefixes
whose type can be specified via the "prefix_type" option. Three sets of
prefixes are available:

binary::
IEC prefixes (Ki, Mi, Gi, Ti) represent multiples of powers of 1024.
This is the default.
decimal::
SI prefixes (k, M, G, T) represent multiples of powers of 1000.
custom::
The custom prefixes (K, M, G, T) represent multiples of powers of 1024.

It is possible to define a low_threshold that causes the disk text to be
displayed using color_bad. The low_threshold type can be of threshold_type
"bytes_free", "bytes_avail", "percentage_free", or "percentage_avail", where
the former two can be prepended by a generic prefix (k, m, g, t) having
prefix_type. So, if you configure low_threshold to 2, threshold_type to
"gbytes_avail", and prefix_type to "binary", and the remaining available disk
space is below 2 GiB, it will be colored bad. If not specified, threshold_type
is assumed to be "percentage_avail" and low_threshold to be set to 0, which
implies no coloring at all. You can customize the output format when below
low_threshold with format_below_threshold.

You can define a different format with the option "format_not_mounted"
which is used if the path does not exist or is not a mount point. Defaults to "".

*Example order*: +disk /mnt/usbstick+

*Example format*: +%free (%avail)/ %total+

*Example format*: +%percentage_used used, %percentage_free free, %percentage_avail avail+

*Example prefix_type*: +custom+

*Example low_threshold*: +5+

*Example format_below_threshold*: +Warning: %percentage_avail+

*Example threshold_type*: +percentage_free+

=== Run-watch

Expands the given path to a pidfile and checks if the process ID found inside
is valid (that is, if the process is running). You can use this to check if
a specific application, such as a VPN client or your DHCP client is running.
There also is an option "format_down". You can hide the output with
+format_down=""+.

*Example order*: +run_watch DHCP+

*Example format*: +%title: %status+

=== Path-exists

Checks if the given path exists in the filesystem. You can use this to check if
something is active, like for example a VPN tunnel managed by NetworkManager.
There also is an option "format_down". You can hide the output with
+format_down=""+.

*Example order*: +path_exists VPN+

*Example format*: +%title: %status+

=== Wireless

Gets the link quality, frequency and ESSID of the given wireless network
interface. You can specify different format strings for the network being
connected or not connected.

The special interface name `_first_` will be replaced by the first wireless
network interface found on the system (excluding devices starting with "lo").

*Example order*: +wireless wlan0+

*Example format*: +W: (%quality at %essid, %bitrate / %frequency) %ip+

=== Ethernet

Gets the IP address and (if possible) the link speed of the given ethernet
interface. If no IPv4 address is available and an IPv6 address is, it will be
displayed. Getting the link speed requires the cap_net_admin capability.
Set it using +setcap cap_net_admin=ep $(which i3status)+.

The special interface name `_first_` will be replaced by the first non-wireless
network interface found on the system (excluding devices starting with "lo").

*Example order*: +ethernet eth0+

*Example format*: +E: %ip (%speed)+

=== Battery

Gets the status (charging, discharging, unknown, full), percentage, remaining
time and power consumption (in Watts) of the given battery and when it's
estimated to be empty. If you want to use the last full capacity instead of the
design capacity (when using the design capacity, it may happen that your
battery is at 23% when fully charged because it’s old. In general, I want to
see it this way, because it tells me how worn off my battery is.), just specify
+last_full_capacity = true+. You can hide seconds in the remaining time and
empty time estimations by setting +hide_seconds = true+.

If you want the battery percentage to be shown without decimals, add
+integer_battery_capacity = true+.

If your battery is represented in a non-standard path in /sys, be sure to
modify the "path" property accordingly, i.e. pointing to the uevent file on
your system. The first occurrence of %d gets replaced with the battery number,
but you can just hard-code a path as well.

It is possible to define a low_threshold that causes the battery text to be
colored red. The low_threshold type can be of threshold_type "time" or
"percentage". So, if you configure low_threshold to 10 and threshold_type to
"time", and your battery lasts another 9 minutes, it will be colored red.

To show an aggregate of all batteries in the system, use "all" as the number. In
this case (for Linux), the /sys path must contain the "%d" sequence. Otherwise,
the number indicates the battery index as reported in /sys.

Optionally custom strings including any UTF-8 symbols can be used for different
battery states. This makes it possible to display individual symbols
for each state (charging, discharging, unknown, full)
Of course it will also work with special iconic fonts, such as FontAwesome.
If any of these special status strings are omitted, the default (CHR, BAT, UNK,
FULL) is used.

*Example order (for the first battery)*: +battery 0+

*Example order (aggregate of all batteries)*: +battery all+

*Example format*: +%status %remaining (%emptytime %consumption)+

*Example format_down*: +No battery+

*Example status_chr*: +⚡ CHR+

*Example status_bat*: +🔋 BAT+

*Example status_unk*: +? UNK+

*Example status_full*: +☻ FULL+

*Example low_threshold*: +30+

*Example threshold_type*: +time+

*Example path (%d replaced by title number)*: +/sys/class/power_supply/CMB%d/uevent+

*Example path (ignoring the number)*: +/sys/class/power_supply/CMB1/uevent+

=== CPU-Temperature

Gets the temperature of the given thermal zone. It is possible to
define a max_threshold that will color the temperature red in case the
specified thermal zone is getting too hot. Defaults to 75 degrees C. The
output format when above max_threshold can be customized with
format_above_threshold.

*Example order*: +cpu_temperature 0+

*Example format*: +T: %degrees °C+

*Example max_threshold*: +42+

*Example format_above_threshold*: +Warning T above threshold: %degrees °C+

*Example path*: +/sys/devices/platform/coretemp.0/temp1_input+

=== CPU Usage

Gets the percentual CPU usage from +/proc/stat+ (Linux) or +sysctl(3)+
(FreeBSD/OpenBSD).

It is possible to define a max_threshold that will color the load
value red in case the CPU average over the last interval is getting
higher than the configured threshold. Defaults to 95. The output
format when above max_threshold can be customized with
format_above_threshold.

It is possible to define a degraded_threshold that will color the load
value yellow in case the CPU average over the last interval is getting
higher than the configured threshold. Defaults to 90. The output format
when above degraded threshold can be customized with
format_above_degraded_threshold.

For displaying the Nth CPU usage, you can use the %cpu<N> format string,
starting from %cpu0. This feature is currently not supported in FreeBSD.

*Example order*: +cpu_usage+

*Example format*: +all: %usage CPU_0: %cpu0 CPU_1: %cpu1+

*Example max_threshold*: +75+

*Example format_above_threshold*: +Warning above threshold: %usage+

*Example degraded_threshold*: +25+

*Example format_above_degraded_threshold*: +Warning above degraded threshold: %usage+

=== Memory

Gets the memory usage from system on a Linux system from +/proc/meminfo+. Other
systems are currently not supported.

As format placeholders, +total+, +used+, +free+, +available+ and +shared+ are
available. These will print human readable values. It's also possible to prefix
the placeholders with +percentage_+ to get a value in percent.

It's possible to define a +threshold_degraded+ and a +threshold_critical+ to
color the status bar output in yellow or red, if the available memory falls
below the given threshold. Possible values of the threshold can be any integer,
suffixed with an iec symbol (+T+, +G+, +M+, +K+). Alternatively, the integer
can be suffixed by a percent sign, which then rets evaluated relatively to
total memory.

If the +format_degraded+ parameter is given and either the critical or the
degraded threshold applies, +format_degraded+ will get used as format string.
It acts equivalently to +format+.

As Linux' meminfo doesn't expose the overall memory in use, there are multiple
methods to distinguish the actually used memory. 

*Example memory_used_method*: +memavailable+ ("total memory" - "MemAvailable", matches +free+ command)

*Example memory_used_method*: +classical+ ("total memory" - "free" - "buffers" - "cache", matches gnome system monitor)

*Example order*: +memory+

*Example format*: +%free %available (%used) / %total+

*Example format*: +%percentage_used used, %percentage_free free, %percentage_shared shared+

*Example threshold_degraded*: +10%+

*Example threshold_critical*: +5%+

*Example format_degraded*: +Memory LOW: %free+

=== Load

Gets the system load (number of processes waiting for CPU time in the last
1, 5 and 15 minutes). It is possible to define a max_threshold that will
color the load value red in case the load average of the last minute is
getting higher than the configured threshold. Defaults to 5. The output 
format when above max_threshold can be customized with
format_above_threshold.

*Example order*: +load+

*Example format*: +%1min %5min %15min+

*Example max_threshold*: +"0,1"+

*Example format_above_threshold*: +Warning: %1min %5min %15min+

=== Time

Outputs the current time in the local timezone.
To use a different timezone, you can set the TZ environment variable,
or use the +tztime+ module.
See +strftime(3)+ for details on the format string.

*Example order*: +time+

*Example format*: +%Y-%m-%d %H:%M:%S+

=== TzTime

Outputs the current time in the given timezone.
If no timezone is given, local time will be used.
See +strftime(3)+ for details on the format string.
The system's timezone database is usually installed in +/usr/share/zoneinfo+.
Files below that path make for valid timezone strings, e.g. for
+/usr/share/zoneinfo/Europe/Berlin+ you can set timezone to +Europe/Berlin+
in the +tztime+ module.
To override the locale settings of your environment, set the +locale+ option.

*Example order*: +tztime berlin+

*Example format*: +%Y-%m-%d %H:%M:%S %Z+

*Example timezone*: +Europe/Berlin+

*Example locale*: +de_DE.UTF-8+

If you would like to use markup in this section, there is a separate
+format_time+ option that is automatically escaped. Its output then replaces
%time in the format string.

*Example configuration (markup)*:
-------------------------------------------------------------
tztime berlin {
        format = "<span foreground='#ffffff'>time:</span> %time"
        format_time = "%H:%M %Z"
        timezone = "Europe/Berlin"
}
-------------------------------------------------------------

=== DDate

Outputs the current discordian date in user-specified format. See +ddate(1)+ for
details on the format string.
*Note*: Neither *%.* nor *%X* are implemented yet.

*Example order*: +ddate+

*Example format*: +%{%a, %b %d%}, %Y%N - %H+

=== Volume

Outputs the volume of the specified mixer on the specified device.  PulseAudio
and ALSA (Linux only) are supported.  If PulseAudio is absent, a simplified
configuration can be used on FreeBSD and OpenBSD due to the lack of ALSA,  the
+device+ and +mixer+ options can be ignored on these systems. On these systems
the OSS API is used instead to query +/dev/mixer+ directly if +mixer_idx+ is
-1, otherwise +/dev/mixer++mixer_idx+.

To get PulseAudio volume information, one must use the following format in the
device line:

 device = "pulse"

or

 device = "pulse:N"

where N is the index or name of the PulseAudio sink. You can obtain the name of
the sink with the following command:

 $ pacmd list-sinks | grep name:
            name: <alsa_output.pci-0000_00_14.2.analog-stereo>

The name is what's inside the angle brackets, not including them. If no sink is
specified the default sink is used. If the device string is missing or is set
to "default", PulseAudio will be tried if detected and will fallback to ALSA
(Linux) or OSS (FreeBSD/OpenBSD).

*Example order*: +volume master+

*Example format*: +♪: %volume+

*Example format_muted*: +♪: 0%%+

*Example configuration*:
-------------------------------------------------------------
volume master {
        format = "♪: %volume"
        format_muted = "♪: muted (%volume)"
        device = "default"
        mixer = "Master"
        mixer_idx = 0
}
-------------------------------------------------------------
*Example configuration (PulseAudio)*:
-------------------------------------------------------------
volume master {
        format = "♪: %volume"
        format_muted = "♪: muted (%volume)"
        device = "pulse:1"
}
-------------------------------------------------------------
-------------------------------------------------------------
volume master {
        format = "♪: %volume"
        format_muted = "♪: muted (%volume)"
        device = "pulse:alsa_output.pci-0000_00_14.2.analog-stereo"
}
-------------------------------------------------------------

== Universal module options

When using the i3bar output format, there are a few additional options that
can be used with all modules to customize their appearance:

align::
        The alignment policy to use when the minimum width (see below) is not
        reached. Either +center+ (default), +right+ or +left+.
min_width::
        The minimum width (in pixels) the module should occupy. If the module takes
        less space than the specified size, the block will be padded to the left
        and/or the right side, according to the defined alignment policy. This is
        useful when you want to prevent the whole status line from shifting when
        values take more or less space between each iteration.
        The option can also be a string. In this case, the width of the given text
        determines the minimum width of the block. This is useful when you want to
        set a sensible minimum width regardless of which font you are using, and at
        what particular size. Please note that a number enclosed with quotes will
        still be treated as a number.
separator::
        A boolean value which specifies whether a separator line should be drawn
        after this block. The default is true, meaning the separator line will be
        drawn. Note that if you disable the separator line, there will still be a
        gap after the block, unless you also use separator_block_width.
separator_block_width::
        The amount of pixels to leave blank after the block. In the middle of this
        gap, a separator symbol will be drawn unless separator is disabled. This is
        why the specified width should leave enough space for the separator symbol.

*Example configuration*:
-------------------------------------------------------------
disk "/" {
    format = "%avail"
    align = "left"
    min_width = 100
    separator = false
    separator_block_width = 1
}
-------------------------------------------------------------

== Using i3status with dzen2

After installing dzen2, you can directly use it with i3status. Just ensure that
+output_format+ is set to +dzen2+.

*Example for usage of i3status with dzen2*:
--------------------------------------------------------------
i3status | dzen2 -fg white -ta r -w 1280 \
-fn "-misc-fixed-medium-r-normal--13-120-75-75-C-70-iso8859-1"
--------------------------------------------------------------

== Using i3status with xmobar

To get xmobar to start, you might need to copy the default configuration
file to +~/.xmobarrc+. Also, ensure that the +output_format+ option for i3status
is set to +xmobar+.

*Example for usage of i3status with xmobar*:
---------------------------------------------------------------------
i3status | xmobar -o -t "%StdinReader%" -c "[Run StdinReader]"
---------------------------------------------------------------------

== What about memory usage or CPU frequency?

While talking about two specific things, please understand this section as a
general explanation why your favorite information is not included in i3status.

Let’s talk about memory usage specifically. It is hard to measure memory in a
way which is accurate or meaningful. An in-depth understanding of how paging
and virtual memory work in your operating system is required. Furthermore, even
if we had a well-defined way of displaying memory usage and you would
understand it, I think that it’s not helpful to repeatedly monitor your memory
usage. One reason for that is that I have not run out of memory in the last few
years.  Memory has become so cheap that even in my 4 year old notebook, I have
8 GiB of RAM. Another reason is that your operating system will do the right
thing anyway: Either you have not enough RAM for your workload, but you need to
do it anyway, then your operating system will swap. Or you don’t have enough
RAM and you want to restrict your workload so that it fits, then the operating
system will kill the process using too much RAM and you can act accordingly.

For CPU frequency, the situation is similar. Many people don’t understand how
frequency scaling works precisely. The generally recommended CPU frequency
governor ("ondemand") changes the CPU frequency far more often than i3status
could display it. The display number is therefore often incorrect and doesn’t
tell you anything useful either.

In general, i3status wants to display things which you would look at
occasionally anyways, like the current date/time, whether you are connected to
a WiFi network or not, and if you have enough disk space to fit that 4.3 GiB
download.

However, if you need to look at some kind of information more than once in a
while (like checking repeatedly how full your RAM is), you are probably better
off with a script doing that, which pops up an alert when your RAM usage reaches
a certain threshold. After all, the point of computers is not to burden you
with additional boring tasks like repeatedly checking a number.

== External scripts/programs with i3status

In i3status, we don’t want to implement process management again. Therefore,
there is no module to run arbitrary scripts or commands. Instead, you should
use your shell, for example like this:

*Example for prepending the i3status output*:
--------------------------------------------------------------
#!/bin/sh
# shell script to prepend i3status with more stuff

i3status | while :
do
        read line
        echo "mystuff | $line" || exit 1
done
--------------------------------------------------------------

Put that in some script, say +.bin/my_i3status.sh+ and execute that instead of i3status.

Note that if you want to use the JSON output format (with colors in i3bar), you
need to use a slightly more complex wrapper script. There are examples in the
contrib/ folder, see https://github.com/i3/i3status/tree/master/contrib

== SIGNALS

When receiving +SIGUSR1+, i3status’s nanosleep() will be interrupted and thus
you will force an update. You can use killall -USR1 i3status to force an update
after changing the system volume, for example.

== SEE ALSO

+strftime(3)+, +date(1)+, +glob(3)+, +dzen2(1)+, +xmobar(1)+

== AUTHORS

Michael Stapelberg and contributors

Thorsten Toepper

Baptiste Daroussin

Axel Wagner

Fernando Tarlá Cardoso Lemos