Blog – Page 129 – TRUEANGLE

pstree – display a tree of processes

ABOUT pstree

pstree shows running processes as a tree.  The tree is rooted at either pid  or  init  if  pid  is
omitted.   If a user name is specified, all process trees rooted at processes owned by that user are
shown.

[bash]
$pstree -A
init-+-NetworkManager—3*[{NetworkManager}]
|-accounts-daemon—2*[{accounts-daemon}]
|-acpid
|-at-spi-bus-laun-+-dbus-daemon
| `-3*[{at-spi-bus-laun}]
|-at-spi2-registr—{at-spi2-registr}
|-atd
|-avahi-daemon—avahi-daemon
|-bluetoothd
|-colord—2*[{colord}]
|-console-kit-dae—64*[{console-kit-dae}]
|-cron
|-2*[dbus-daemon]
|-dbus-launch
|-dconf-service—2*[{dconf-service}]
|-dhclient
|-evolution-addre—4*[{evolution-addre}]
|-evolution-calen—4*[{evolution-calen}]
|-evolution-sourc—2*[{evolution-sourc}]
|-exim4
|-gconfd-2
|-gdm3-+-gdm-simple-slav-+-Xorg—{Xorg}
| | |-gdm-session-wor-+-gnome-session-+-applet.py—{applet.py}
| | | | |-evolution-alarm—4*[{evolution-alarm}]
| | | | |-gnome-settings—-3*[{gnome-settings-}]
| | | | |-gnome-shell-+-chrome-+-chrome
| | | | | | |-chrome-sandbox—chro+
| | | | | | `-39*[{chrome}]
| | | | | `-6*[{gnome-shell}]
| | | | |-ssh-agent
| | | | |-tracker-store—7*[{tracker-store}]
| | | | `-3*[{gnome-session}]
| | | `-2*[{gdm-session-wor}]
| | `-2*[{gdm-simple-slav}]
| `-2*[{gdm3}]
|-6*[getty]
|-gnome-keyring-d—7*[{gnome-keyring-d}]
|-gnome-shell-cal—4*[{gnome-shell-cal}]
|-gnome-terminal–+-bash—emacs
| |-bash—pstree
| |-gnome-pty-helpe
| `-3*[{gnome-terminal-}]
|-goa-daemon—3*[{goa-daemon}]
|-gpm
|-gsd-printer—{gsd-printer}
|-gvfs-afc-volume—2*[{gvfs-afc-volume}]
|-gvfs-goa-volume—{gvfs-goa-volume}
|-gvfs-gphoto2-vo—{gvfs-gphoto2-vo}
|-gvfs-mtp-volume—{gvfs-mtp-volume}
|-gvfs-udisks2-vo—2*[{gvfs-udisks2-vo}]
|-gvfsd—{gvfsd}
|-gvfsd-burn—2*[{gvfsd-burn}]
|-mission-control—2*[{mission-control}]
|-modem-manager
|-ntpd
|-polkitd—2*[{polkitd}]
|-pulseaudio—2*[{pulseaudio}]
|-rsyslogd—3*[{rsyslogd}]
|-rtkit-daemon—2*[{rtkit-daemon}]
|-sshd
|-systemd-logind
|-udevd
|-udisksd—4*[{udisksd}]
|-upowerd—2*[{upowerd}]
`-wpa_supplicant
$
[/bash]

UNIX Explanation

pstree  shows running processes  as a  tree. The  tree is rooted at either pid or init if pid is omitted.
If a user name is specified, all  process trees rooted at processes owned by that user are shown.

RELATED SOURCE CODE EXPOSITION
[c]
static void free_buffers()
{
if (width != NULL) {
free(width);
width = NULL;
}
if (more != NULL) {
free(more);
more = NULL;
}
capacity = 0;
}
[/c]

SOURCE CODE HIGHLIGHT

Frees any buffers allocated by ensure_buffer_capacity.

RELATED KNOWLEDGE

The   fundamental  data   structure  within   the  kernel controlling all processes is the process
structure, which grows and shrinks dynamically as processes are forked and finished or killed.

LINKS
https://www.howtoforge.com/linux-pstree-command/
http://man7.org/linux/man-pages/man1/pstree.1.html

pstree – process status tree

Linux Command

systemd-+-ModemManager---3*[{ModemManager}]
        |-NetworkManager---3*[{NetworkManager}]
        |-accounts-daemon---3*[{accounts-daemon}]
        |-avahi-daemon---avahi-daemon
        |-bluetoothd
        |-colord---3*[{colord}]
        |-cron
        |-cups-browsed---3*[{cups-browsed}]
        |-cupsd
        |-dbus-daemon
        |-exim4
        |-fwupd---5*[{fwupd}]
        |-gdm3-+-gdm-session-wor-+-gdm-x-session-+-Xorg---13*[{Xorg}]
        |      |                 |               |-gnome-session-b-+-ssh-agent
        |      |                 |               |                 `-4*[{gnome-session-b}]
        |      |                 |               `-3*[{gdm-x-session}]
        |      |                 `-3*[{gdm-session-wor}]
        |      `-3*[{gdm3}]
        |-geoclue---3*[{geoclue}]
        |-gpm
        |-nm-dispatcher---4*[{nm-dispatcher}]
        |-polkitd---3*[{polkitd}]
        |-power-profiles----3*[{power-profiles-}]
        |-rsyslogd---3*[{rsyslogd}]
        |-rtkit-daemon---2*[{rtkit-daemon}]
        |-sshd
        |-switcheroo-cont---3*[{switcheroo-cont}]
        |-systemd-+-(sd-pam)
        |         |-at-spi-bus-laun-+-dbus-daemon
        |         |                 `-4*[{at-spi-bus-laun}]
        |         |-at-spi2-registr---3*[{at-spi2-registr}]
        |         |-dbus-daemon
        |         |-dconf-service---3*[{dconf-service}]
        |         |-evolution-addre---6*[{evolution-addre}]
        |         |-evolution-calen---9*[{evolution-calen}]
        |         |-evolution-sourc---4*[{evolution-sourc}]
        |         |-gcr-ssh-agent---2*[{gcr-ssh-agent}]
        |         |-2*[gjs---11*[{gjs}]]
        |         |-gnome-keyring-d---4*[{gnome-keyring-d}]
        |         |-gnome-session-b-+-evolution-alarm---7*[{evolution-alarm}]
        |         |                 |-gnome-software---16*[{gnome-software}]
        |         |                 |-gsd-disk-utilit---3*[{gsd-disk-utilit}]
        |         |                 `-4*[{gnome-session-b}]
        |         |-gnome-session-c---{gnome-session-c}
        |         |-gnome-shell-+-firefox-+-Isolated Servic---20*[{Isolated Servic}]
        |         |             |         |-Isolated Web Co---23*[{Isolated Web Co}]
        |         |             |         |-3*[Isolated Web Co---17*[{Isolated Web Co}]]
        |         |             |         |-3*[Isolated Web Co---18*[{Isolated Web Co}]]
        |         |             |         |-Privileged Cont---18*[{Privileged Cont}]
        |         |             |         |-RDD Process---3*[{RDD Process}]
        |         |             |         |-Socket Process---4*[{Socket Process}]
        |         |             |         |-Utility Process---3*[{Utility Process}]
        |         |             |         |-3*[Web Content---10*[{Web Content}]]
        |         |             |         |-WebExtensions---17*[{WebExtensions}]
        |         |             |         `-182*[{firefox}]
        |         |             |-mutter-x11-fram---14*[{mutter-x11-fram}]
        |         |             `-35*[{gnome-shell}]
        |         |-gnome-shell-cal---6*[{gnome-shell-cal}]
        |         |-gnome-terminal--+-bash---git-+-git---git-remote-http
        |         |                 |            |-git
        |         |                 |            `-{git}
        |         |                 |-bash---pstree
        |         |                 `-5*[{gnome-terminal-}]
        |         |-goa-daemon---4*[{goa-daemon}]
        |         |-goa-identity-se---3*[{goa-identity-se}]
        |         |-gsd-a11y-settin---4*[{gsd-a11y-settin}]
        |         |-gsd-color---4*[{gsd-color}]
        |         |-gsd-datetime---4*[{gsd-datetime}]
        |         |-gsd-housekeepin---4*[{gsd-housekeepin}]
        |         |-gsd-keyboard---4*[{gsd-keyboard}]
        |         |-gsd-media-keys---5*[{gsd-media-keys}]
        |         |-gsd-power---5*[{gsd-power}]
        |         |-gsd-print-notif---3*[{gsd-print-notif}]
        |         |-gsd-printer---3*[{gsd-printer}]
        |         |-gsd-rfkill---3*[{gsd-rfkill}]
        |         |-gsd-screensaver---3*[{gsd-screensaver}]
        |         |-gsd-sharing---4*[{gsd-sharing}]
        |         |-gsd-smartcard---4*[{gsd-smartcard}]
        |         |-gsd-sound---4*[{gsd-sound}]
        |         |-gsd-usb-protect---4*[{gsd-usb-protect}]
        |         |-gsd-wacom---3*[{gsd-wacom}]
        |         |-gsd-xsettings---4*[{gsd-xsettings}]
        |         |-gvfs-afc-volume---4*[{gvfs-afc-volume}]
        |         |-gvfs-goa-volume---3*[{gvfs-goa-volume}]
        |         |-gvfs-gphoto2-vo---3*[{gvfs-gphoto2-vo}]
        |         |-gvfs-mtp-volume---3*[{gvfs-mtp-volume}]
        |         |-gvfs-udisks2-vo---4*[{gvfs-udisks2-vo}]
        |         |-gvfsd-+-gvfsd-dnssd---3*[{gvfsd-dnssd}]
        |         |       |-gvfsd-network---4*[{gvfsd-network}]
        |         |       |-gvfsd-trash---4*[{gvfsd-trash}]
        |         |       `-3*[{gvfsd}]
        |         |-gvfsd-fuse---6*[{gvfsd-fuse}]
        |         |-gvfsd-metadata---3*[{gvfsd-metadata}]
        |         |-ibus-daemon-+-ibus-dconf---4*[{ibus-dconf}]
        |         |             |-ibus-engine-sim---3*[{ibus-engine-sim}]
        |         |             |-ibus-extension----4*[{ibus-extension-}]
        |         |             `-3*[{ibus-daemon}]
        |         |-ibus-portal---3*[{ibus-portal}]
        |         |-ibus-x11---3*[{ibus-x11}]
        |         |-jackdbus
        |         |-2*[pipewire---2*[{pipewire}]]
        |         |-pipewire-pulse---2*[{pipewire-pulse}]
        |         |-sd_dummy---2*[{sd_dummy}]
        |         |-sd_espeak-ng---{sd_espeak-ng}
        |         |-speech-dispatch---4*[{speech-dispatch}]
        |         |-tracker-miner-f---7*[{tracker-miner-f}]
        |         |-wireplumber---5*[{wireplumber}]
        |         |-xdg-desktop-por---6*[{xdg-desktop-por}]
        |         |-xdg-desktop-por---14*[{xdg-desktop-por}]
        |         |-xdg-desktop-por---4*[{xdg-desktop-por}]
        |         |-xdg-document-po-+-fusermount3
        |         |                 `-6*[{xdg-document-po}]
        |         `-xdg-permission----3*[{xdg-permission-}]
        |-systemd-hostnam
        |-systemd-journal
        |-systemd-logind
        |-systemd-timesyn---{systemd-timesyn}
        |-systemd-udevd
        |-udisksd---5*[{udisksd}]
        |-unattended-upgr---{unattended-upgr}
        |-upowerd---3*[{upowerd}]
        `-wpa_supplicant

Explanation

pstree  shows running processes  as a  tree. The  tree is
rooted at either pid or init if pid is omitted. If a user
name is specified, all  process trees rooted at processes
owned by that user are shown.

Related Source Code Exposition `static void free_buffers() { if (width != NULL) { free(width); width = NULL; } if (more != NULL) { free(more); more = NULL; } capacity = 0; }`

Source Code Highlight

Frees any buffers allocated by ensure_buffer_capacity.

Featured Image

Related Knowledge

The   fundamental  data   structure  within   the  kernel
controlling all processes is the process structure, which
grows and shrinks dynamically as processes are forked and
finished or killed.

GOOD NEWS

Good News

 
It is in living and acting that man establishes his relationship with 
being, with the truth and with the good. The artist has a special
relationship to beauty. In a very true sense it can be said that beauty is
the vocation bestowed on him by the Creator in the gift of “artistic 
talent”. And, certainly, this too is a talent which ought to be made to
] bear fruit, in keeping with the sense of the Gospel parable of the
talents (cf. Mt 25:14-30)
.

Here we touch on an essential point. Those who perceive in themselves this
kind of divine spark which is the artistic vocation—as poet, writer,
sculptor, architect, musician, actor and so on—feel at the same time the
obligation not to waste this talent but to develop it, in order to put it
at the service of their neighbour and of humanity as a whole
.

John Paul II  Letter to Artists, (April 4, 1999)
The artistic vocation in the service of beauty

IDEA

Vision . [ sirach  11:20 ] from  New American Bible
My son, hold fast to your duty, busy yourself with it, grow old while doing your task.
Our part : By doing the above we will be free from worries.

Mission.
directing passion to path  of knowledge and self realization.

Objective(s).
Acquire In Depth Knowledge of software operating systems
and functions with the help of systems administration.

Acquire In Depth Knowledge of how Internet Works
using Web Development.

strive  to transform systems administration into a science.