Is "ctl" in systemctl an acronym for "control"? I couldn't find the meaning of systemctl on Wikipedia.

What do the terms "in-tree" and "out-of-tree" exactly mean? Also, does "source tree" specifically refer to the official kernel released from / maintained at kernel.org or is it a more general term which can refer to any (modified) Linux kernel source?

I noticed when using virsh that VMs are referred to as "domains". Why are they called that instead of "virtual machines"? $ virsh virsh # help ... Domain Monitoring (help keyword 'monitor'): domblkerror Show errors on block devices domblkinfo domain block device size information domblklist list all domain blocks domblkstat get device block stats for a domain domcontrol domain control interface state domif-getlink get link state of a virtual interface domifaddr Get network interfaces' addresses for a running domain domiflist list all domain virtual interfaces domifstat get network interface stats for a domain dominfo domain information dommemstat get memory statistics for a domain domstate domain state domstats get statistics about one or multiple domains domtime domain time list list domains ... virsh # list --all Id Name State ---------------------------------------------------- - centos_vagrant_test_test_vm shut off - collectd01 shut off - grafana01 shut off - influxdb01 shut off - JobDBWin7_Stable shut off - OpenWRT_Red shut off

Is there a difference between a "dot file" and a "configuration file"? For example, I have torrc file in /opt/homebrew/etc/tor. Neither filename itself nor any of its parent directories start with a dot. Nevertheless, this file is the same as .vimrc is for Vim. Is it correct to call it a dot file?

I keep hearing people talk about "recursion" for example, when you copy and paste a file and a directory you need to also put in the -r flag to tell the cp command to copy the directory "recursively" I look up the word "recursion" and I get this > recursion is when a function can call itself and then people tell me about russian dolls and how recursion is like a program inside a program like a russian doll is like a doll inside a doll. So my question is, what does "recursion" mean when it's applied to the bash shell? I don't understand how the concept of "recursion" applies to bash or the programs in bash for example when I cp a file and a directory and I have to put the -r flag in with cp to make sure that the file AND the directory gets copied

I'm a little confusing about the tape options in Unix EOM (end of mark) EOT (end of tape) PEOT (physical end of tape) As I understand EOM is the the end of last file, but I have also some free tape EOT is the end of tape, no more space available PEOT is the same of EOT, correct?

I am not sure I correctly understood what is a *path name component* (or perhaps better written; *path name-component*) which I understand to be commonly abbreviated simply as "component" in the Unix & Linux literature. > **My understanding so far** > > A *directory* file or an *archive* file for that > matter are both *aggregated files* ("container files"), which can > contain one file or two or more files, in *depth* 1 and possibly in > deeper depths as well. > > Any possible file (say, an aggregated file > or its sub-directory or its sub-archive or even its > sub-file of whatever other kind) can have either of these path name-component *kinds*: > > * Singular (forwardslash**less**) > * Plural: Two sub-path-components separated by one forward slash or three or more sub-path-components separated by two or more forward slashes > > If a file has a *singular* or *plural*, or not, path name component, > is relatively depends on depth. What is a "path name component"?

I am attempting to store some large files and I thought an encrypted ext4 partition would be excellent. However the GNOME Disk Utility appears to state ext4 as for internal disks and xfs only for Linux filesystems. Can I utilize them both safely with removable media? Is there one that is more utilitarian for this usage? What makes them different? _________________ Thank you so much for any information you can provide.

i keep hearing people talking about "strings"? what is a string? what are people talking about? i keep hearing "enter a string" or "if your string this" or your "string that"? what does it mean to enter a string in bash? any help would be appreciated, i'm genuinely confused at what it's supposed to mean when i ask google it tells me "Bash String is a data type similar to integer or boolean. " and i have no idea what this is supposed to mean thank you

I came across a confusing variation in the understanding what options and arguments are with regard to the syntax of commands. For instance, I encountered definitions like: - command -a -b -c d e f some differ between -a -b -c, call them options or switches and d e f by calling them arguments. - command -a -b -c d e f some, for instance a bash manual, call all -a -b -c d e f arguments and explains, that all of them are accessible from a script by $1 $2 $3 $4 $5 $6 respectively. - command -a b=c some call -a an option, b an argument and c the value, but others mix them like in the first two points, in one variety calling all -a b c arguments. Those three versions are only examples for a plethora of different calling varieties, I do not even know how to list them all, but I noticed that for sure there is no fixed naming convention. Or at least, there is no standardised naming convention I know about, because I came across different random sources, but even among official Linux and GNU affiliated sites or manuals I could met this inconsistency. Is there a unquestionable official naming scheme I can refer to?

so i keep hearing that a flag is a TYPE of option, and that the only difference between a flag and normal options is that a flag is a type of "boolean" option, which when explained to me seems no different then binary so what is a flag? how is it different then other options? what would be a good example to show someone in the terminal the difference between flags and other types of options? thank you

I'm trying to figure out the correct term(s) for Unix/Linux "commands." Specifically, I have always understood that technically *commands* (e.g., cd) are built into the shell, and that other "commands" (e.g., rm, ls, mkdir, cp, mv) are better termed *utilities*, as they are stand-alone programs. (As far as I can tell, rm, etc. are all in /bin.) Furthermore, one way to tell whether something is a command is to see if it has a man page: commands don't, but utilities do. However, all of the sources I've found via Google use "commands" exclusively. Can someone set me straight on this or point me towards an appropriate reference? Since exit doesn't have a man page and isn't in /bin, is it, like cd, a true command?

this question may be a bit terminological. As a new Linux learner, I find many tutorials mention Linux/bash commands. To my understanding, commands are just various programs and bash is a shell like zsh, fish etc. on Linux. Shell will interpret user input and call corresponding program. So Linux commands are things like cd, mkdir, while bash commands are somewhat specific to the shell syntax. For example, if someone would like, he/she could build a shell requiring run cd instead of cd just doing the same thing. Is my understanding precise? PS: I think I can understand the concept of terminal/shell/command line, which have stated in many other questions, and I believe this question is different from those.

1. May I know what are the meaning of 'fixed" and "obsolete" in debsecan of Ubuntu? **output of "debsecan --suite bookworm"**
a) CVE-2024-xxxxx {Package Name} (fixed, obsolete)
b) CVE-2024-xxxxx {Package Name} (fixed)
c) CVE-2024-xxxxx {Package Name} (obsolete) And is the vulnerability fixed?

$ debsecan --suite bookworm --format detail


CVE-2021-33061
  Insufficient control flow management for the Intel(R) 82599 Ethernet C ...
  installed: linux-headers-5.15.0-100-generic 5.15.0-100.110
             (built from linux 5.15.0-100.110)
             package is obsolete
  fixed in unstable: linux 5.18.2-1 (source package)


CVE-2021-33631
  Integer Overflow or Wraparound vulnerability in openEuler kernel on Li ...
  installed: linux-headers-5.15.0-102-generic 5.15.0-102.112
             (built from linux 5.15.0-102.112)
             package is obsolete
  fixed in unstable: linux 6.1.4-1 (source package)
  fixed on branch:   linux 4.19.282-1 (source package)
  fixed on branch:   linux 4.19.289-1 (source package)
  fixed on branch:   linux 4.19.289-2 (source package)
  fixed on branch:   linux 4.19.304-1 (source package)
  fixed on branch:   linux 4.19.316-1 (source package)
  fixed on branch:   linux 5.10.178-1 (source package)
  fixed on branch:   linux 5.10.179-1 (source package)
  fixed on branch:   linux 5.10.179-2 (source package)
  fixed on branch:   linux 5.10.179-3 (source package)
  fixed on branch:   linux 5.10.179-5 (source package)
  fixed on branch:   linux 5.10.191-1 (source package)
  fixed on branch:   linux 5.10.197-1 (source package)
  fixed on branch:   linux 5.10.205-1 (source package)
  fixed on branch:   linux 5.10.205-2 (source package)
  fixed on branch:   linux 5.10.209-1 (source package)
  fixed on branch:   linux 5.10.209-2 (source package)
  fixed on branch:   linux 5.10.215-1 (source package)
  fixed on branch:   linux 5.10.216-1 (source package)
  fixed on branch:   linux 5.10.218-1 (source package)
  fixed on branch:   linux 5.10.221-1 (source package)

Installed Package:

$ apt list --installed | fgrep linux-headers

linux-headers-5.15.0-100-generic/jammy-updates,jammy-security,now 5.15.0-100.110 amd64 [installed]
linux-headers-5.15.0-100/jammy-updates,jammy-security,now 5.15.0-100.110 all [installed]
linux-headers-5.15.0-102-generic/jammy-updates,jammy-security,now 5.15.0-102.112 amd64 [installed]
linux-headers-5.15.0-102/jammy-updates,jammy-security,now 5.15.0-102.112 all [installed]
linux-headers-5.15.0-113-generic/jammy-updates,jammy-security,now 5.15.0-113.123 amd64 [installed,automatic]
linux-headers-5.15.0-113/jammy-updates,jammy-security,now 5.15.0-113.123 all [installed,automatic]
linux-headers-5.15.0-118-generic/jammy-updates,jammy-security,now 5.15.0-118.128 amd64 [installed,automatic]
linux-headers-5.15.0-118/jammy-updates,jammy-security,now 5.15.0-118.128 all [installed,automatic]
linux-headers-5.15.0-97-generic/jammy-updates,jammy-security,now 5.15.0-97.107 amd64 [installed]
linux-headers-5.15.0-97/jammy-updates,jammy-security,now 5.15.0-97.107 all [installed]
linux-headers-generic/jammy-updates,jammy-security,now 5.15.0.118.118 amd64 [installed,automatic]

Assume that this command invokes an application from the MacOS terminal command line: /Applications/Matlab_R2020a.app/bin/matlab The terminal then is no longer able to accept commands and MATLAB is dependent (i.e. will terminate if the terminal console is closed). What is this dependency called and how can the application be started so that it will be "independent"? That is, closing the terminal will not close the application?

From man bash (GNU bash, version 5.2.21(1)-release (x86_64-pc-cygwin)):

set [-abefhkmnptuvxBCEHPT] [-o option-name] [--] [-] [arg ...]
  -a  Each variable or function that is created or modified is given the export
      attribute and marked for export to the environment of subsequent commands.

export [-fn] [name[=word]] ...
export -p
      The supplied names are marked for automatic export to the environment of
      subsequently executed commands.

Here we see that export doesn't "give the export attribute" while set -a does. Why? Is it an oversight? Extra question: what's the difference between "export" and "automatic export"? (Should both be "export"? Should both be "automatic export"?)

When documenting command-line things, it is often necessary to use generic names. Sometimes I use input and output words, and they play nice:

# example 1
pandoc input_file.md -o output_file.htm

But sometimes they don't play nice, and I use source and target instead:

# example 2
mv source_file.txt target_folder/

I have two questions here. The first question is whether it is fine (from the side of English language, which is a foreign one for me, logic, etc.) to use source and target pair only? Is it correct to say that this pair of words is more versatile then input and output? The second question is whether it is fine to use target when we don't use source? For example:

# example 3. ImageMagick will copy all the .jpg and .png files
# to target_folder, and then trim them there
magick mogrify -path target_folder/ -trim +repage *.(jpg|png)

I don't know how exactly to describe it verbally, but I just mean the white triangular arrows in this example image: \ In an icon theme that I'm trying to use they either don't exist or are the exact same color as the menus that they're on top of. I don't know how to look up what their standard filename is in GNOME/GTK/whatever icon sets because I also have no idea what they're called in a general sense.  I just want to go into that theme's folder in /usr/share/icons and either put them there or replace them with ones that are actually visible.

My understanding is that a _file descriptor_ is an integer which is a key in the kernel's per-process mapping to objects such as open()ed files, pipes, sockets, etc. Is there a proper, short, and specific name for “open files/sockets/pipes/...”, the referents of file descriptors? Calling them “files” leads to confusion with unopened files stored in the file system. Simply referring to file descriptors does not adequately describe the semantics (e.g. copying *the integer* between processes is useless). Consulting [The Open Group Base Specifications](http://pubs.opengroup.org/onlinepubs/009695399/) and my own system's manpages leads me to the conclusion that the referent of a file descriptor is an _object_ and when it is specifically an open file it is, well, an _open file_. Is there a more specific term than _object_?

I've noticed that throughout the Internet, within forums and blog posts, Unix always has a * in the word, whether it is \*nix or Un\*x, as I noticed at the welcoming banner at the Unix StackExchange site. Why is this like this?