Stands for in linux

What does etc stand for?

What does the «etc» folder in the root directory stand for? I think knowing this will help me remember where certain files are located. Update: Might be useful for others, the folder is used for «Host specific configuration files» — reference.

A backronym I rather like is «Edit To Configure», but there is no history to suggest that this is a «real» meaning.

My guess would be history. Nobody really thought «Hey, we’re going to have a bunch of system-wide config data!» and so nobody ever created a directory for it. But, of course, there was, and everybody shoved it into /etc because there wasn’t anyplace else to put it. Poof! De-facto standard. You know that /usr was originally the place where user home directories were?

It’s also (slightly) interesting to note that older versions of Solaris and HP-UX (and maybe others that I’ve forgotten) actually had binaries in /etc too.

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Originally, there was /bin for programs (essentially, executable binaries), and very soon /dev for device files and /lib for extra executable code loaded by programs (libraries). /usr also came in very early, first for user data, then as an extra OS area with its own bin and lib and then man containing the manual in electronic form. The source code was also often provided somewhere under /usr .

And there were a few files in the operating system that didn’t fit in any of the existing categories. This included a passwd file containing users’ passwords, and an mtab file written by mount , and the init and later rc programs executed at boot time, and over time more and more programs that were intended to be executed only for administration purpose and not as part of normal usage.

(You can browse some old Unix source code on the Unix Tree. Versions earlier than V6 are very fragmentary. You can also see V1 and V6 manuals at the Manual Page Library.)

At first, there was no connotation that files in /etc were configuration files. In these very early days, if you wanted to customize something, you’d be recompiling that part of the system. As Unix got more powerful, there were more and more things you could do without recompiling. As Unix got used more widely, there were more and more things people wanted to do, and they found ways of doing them without going through the trouble of recompiling. So /etc filled up with more and more text files that people could and did customize, hence it gradually became the configuration directory.

With the creation of /sbin to contain programs intended only for the system administrator, /etc ended up containing only text files, many of which can be customized by the system administrator. A few files (e.g. /etc/mtab , sometimes /etc/resolv.conf ) are automatically maintained by system programs; there is a slow trend to move these files to /run in the Linux world.

On modern unix systems, almost all system-wide configuration files are under /etc , but not all files in /etc are configuration files. Typical Linux distributions and other unix variants don’t cope very well with modifying many of the files that come from packages; at a minimum, you may end up having to merge local modifications manually when the system is upgraded.

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What does /etc stands for in Linux/Unix ?

There is a discussion going on over at Slashdot regarding what /etc in Linux/Unix stands for. Is it an acronym or does it stand for ‘et cetera’ ? While the opinion is divided, the overwhelming thought is that it stands for et cetera. That is, what ever data which doesn’t belong to other directories are put into /etc. Such as the ‘motd’ file (which stands for «Message Of The Day»). Many of us also look at /etc as a placeholder for the configuration files of programs which we run on our system.

Linux File System Hierarchy

If you look at the Linux file hierarchy, you find the following :

/sbin — Binaries used for system administration are placed here.

/boot — Static files of the boot loader. Usually it contain the Linux kernel, Grub boot loader files and so on.

/dev — Device files such as your CD drive, hard disk, and any other physical device.

In Linux/Unix, the common premise is that everything is a file.

/home — User HOME directories are found here. In unices like FreeBSD, the HOME directories are found in /usr/home. And in Solaris it is in /export. So quite a big difference here.

/lib — Essential shared libraries and kernel modules.

/mnt — Temporary mount point useful for when you insert your USB stick and it gets mounted under /mnt. Though in Ubuntu and the likes, it is usually mounted under /media.

/var — Variable data, such as logs, news, mail spool files and so on which is constantly being modified by various programs running on your system.

/tmp — Temporary files are placed here by default.

/usr — The secondary hierarchy which contain its own bin and sbin sub-directories.

/etc — Usually contain the configuration files for all the programs that run on your Linux/Unix system.

/opt — Third party application packages which does not conform to the standard Linux file hierarchy can be installed here.

/srv — Contains data for services provided by the system.

And of course there is the /proc directory which does not actually reside on the disk.

The file system hierarchy standard [FSHS] explains /etc as follows :

The /etc hierarchy contains configuration files. A «configuration file» is a local file used to control the operation of a program; it must be static and cannot be an executable binary.

It further goes on to say :

• opt Configuration for /opt
• X11 Configuration for the X Window system (optional)
• sgml Configuration for SGML (optional)
• xml Configuration for XML (optional)

While this is the long and short of the matter, some believe that ‘/etc’ is indeed an acronym and stands for «Editable Text Configuration». Oh well, the media is still not out with the verdict.

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What is Ctl in Linux?

If you are confused about what CTL means in Linux, you can find out the definition of this command in Wikipedia or by using a search engine. Ctl stands for Cargo-Terminal-Lehmann. This command is used to open the command shell. The meaning of CTL varies based on the context. If you are unsure of the exact meaning of CTL, you can try searching for it with certain question structures.

Related Questions / Contents

What Does CTL Stand For?

What does CTL stand for in Linux? You may be wondering if this command will delete the current line’s text, or if it will log you out of the current session. The answers to these questions will be different in different environments. This article will discuss some common uses of Ctl. To find out the meaning of CTL in Linux, you can visit Wikipedia or Google. If you don’t find a meaning for CTL on the first page, you can try other ways to look up the meaning of CTL.

CTL is an acronym for Control Temporal Logic. The CTL file format was designed for classical CTL formulae description. CTL files have two parts: the declaration part, which describes types and constants, and the formulae statement, which contains the CTL formulae. Then, you can use any of the resulting files to perform your desired actions. Often, these files are stored in the system’s /var/log directory.

What is CTL in Ubuntu?

The acronym CTL stands for Control Temporal Logic. The file format is composed of two parts: a formulae statement and declaration. The formulae statement describes the CTL formulae to be checked, and the declaration part includes a boolean operator ‘-‘. The first part is used to declare that the file is a CTL file, while the second part is used to define the formulae.

What is Systemctl Commands?

What are Systemctl commands in Linux? The systemctl command allows users to interact with the systemd process that manages the state of the operating system. It is the primary point of interaction for system state management. There are many different commands that you can use in systemctl. To learn more about them, read on. Below is a list of systemctl commands. These commands can be used to change system settings.

Systemctl is the command used to manage services and system configuration. Systemctl commands let you control service configuration and troubleshoot your operating system. By default, systemctl shows you only running processes. Using systemctl, you can control the status of known services and systemd bus interfaces. To use systemctl, you need administrator-level permissions. The following examples demonstrate how to use systemctl.

The list-units command lists units. Each unit has a name, load status, and general and low-level activation state. System unit files are stored in the /lib/systemd/system directory. User-provided units are stored in /etc/systemd/system directory. This command lists all systemd units. Using the -a option, you can view their configuration.

What is CTL Embedded System?

A Linux embedded system can run programs in the background. These programs are traditionally called daemons. These programs are started by the init program, which is a user-interactive program. There are generally only a handful of user-interactive programs in an embedded system. These programs make the device do what it’s supposed to do, by invoking the necessary components. The following sections describe each of these programs and what they do.

The first part of the series is an overview of embedded Linux. This article describes the major components of an embedded Linux system and the interactions among them. It doesn’t assume prior knowledge about these topics. Instead, it assumes that the reader has a general understanding of Linux and has some familiarity with the kernel. Hopefully, the article will help guide your decision-making process in developing embedded Linux applications. You may also want to visit the other articles in the series to learn more about Linux for embedded systems.

What Does CTL Stand For in Electronics?

In the world of electronics, the abbreviation “CTL” stands for “Complementary Transistor Logic”. In simple terms, this means that one circuit is made up of two similar components that each have different functions. In this article, we’ll cover what CTL means in electronics, and how to find the full meaning of a certain acronym. By the time you’re finished reading this, you’ll have a much better understanding of what this acronym stands for.

What is Systemd And Systemctl?

As you might have guessed, systemd and systemctl are two commands used to manage the systemd service manager. Systemd is a system management platform for UNIX-like systems and is the successor to the old System V init daemon. It provides detailed information about the server-wide usage of various systemd services. The systemctl command does not return output when successful but returns an error message when it fails.

In a nutshell, systemd units represent resources that it knows how to manage. As of this writing, most Linux distributions use SystemD by default. After initializing, SystemD runs as a daemon process and actively tracks services using cgroups. Users interact with SystemD through the systemctl command. In this article, we’ll explore the differences between SystemD and systemctl.

The systemctl command lists the state of units. For example, if a unit is running, systemctl will return “active.” If it’s not, it will return “failed.” If a unit has been intentionally stopped or turned off, systemctl will return “unknown”. If a unit is disabled, systemctl can also start and stop it. When it starts and stops, it uses the root path to search for unit files.

What is Systemd Vs Systemctl?

You might wonder what the difference is between systemd and systemctl. Systemd manages system services, whereas systemctl maintains the state of known services. Both are useful in various ways, and the following sections provide an overview of the main differences. This article is written by Sandra Henry-Stocker, who has been administrating Unix systems for more than 30 years. She lives in the mountains of Virginia where she chases bears away from her bird feeders.

Both systemctl and systemd allow you to start and stop systems. Systemctl uses service unit files to start and stop services. The -user option starts or stops the unit, and systemctl looks for them in order. The -user flag makes it possible to enable or disable a custom service. To enable a custom service, place its service unit file in the /etc/systemd/system directory. Both systemctl and systemd are integral parts of Linux, and most major distributions now use this feature.

What’s the difference between systemctl and service? The first one is a higher-level command. Service initiates startup sequence elements and runs them simultaneously. The latter makes use of D-Bus and Unix domain sockets. A snapshot of the system’s state can be saved for future recall. When running systemctl, you’ll be able to control and manage systemd, including its configuration and services.

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