The origin of the/usr file directory in Unix/linux

In the Linux system, there is a very important directory--/usr directory. On the origin of the name of this directory, there are several main online statements:

• User's abbreviation
• User shareable read-only abbreviation
• Unix/user abbreviation for System resources
• Abbreviation for Unix/user software resources

Most versions of Linux/USR are currently located in the executable and first-close libraries, so the user seems unlikely.

Read the relevant information, the statement about the origin of the/USR directory is as follows:

/usr usually contains by far the largest share of data on a system.
Hence, the one of the most important directories in the system as
It contains all the user binaries, their documentation, libraries,
header files, etc .... X and its supporting libraries can be found
Here. User programs like Telnet, FTP, etc .... is also placed here. Inch
The original Unix implementations,/USR was where the home directories
Of the users were placed (that's to say,/usr/someone were then the
Directory now known As/home/someone). In current unices,/usr is
where User-land programs and data (as opposed to "system land"
Programs and data) are.the name hasn ' t changed, but it's meaning has
Narrowed and lengthened from "Everything user related" to "user usable
Programs and Data ". As such, some people may now refer
Directory as meaning ' user System Resources ' and not ' user ' as is
Originally intended.

/usr is shareable, read-only data. That means that/usr should be
Shareable between various fhs-compliant hosts and must not being written
To. Any information this is host-specific or varies with time is
Stored elsewhere.
Large software packages must not use a direct subdirectory under the
/usr hierarchy.

The/usr directory holds important binaries, documents, library files, header files, and so on in the system. In the early UNIX version, the/usr directory exists as the user's home directory (equivalent to the current///////directory), so the name of the directory should initially be the user's initials, representing the users ' home directory. Now in the UNIX version, the/usr directory has a very different role, the main storage is some non-system startup necessary programs and data. So some people have extended the meaning of the/usr directory to the user System Resources.

The/usr directory holds shared, read-only data. This means that/usr should be shared between hosts that are compatible with the FHS standard, and that the data in it should not be modified. Those data that are related to host properties or that are constantly changing should not be stored in the secondary directory.

Large packages should not be stored in sub-directories under/usr.

Since then, the origin of the/usr directory is the truth. You can call it user System resources or user shareable read-only. Whatever, it's good to know its history and function.

The origin of the/usr file directory in Unix/linux