What Is a Virtual Access Point?

The e-mail address of the virtual folder technology contains a folder called "Unread Mail", which directly lists all unread mail. However, the difference from general folders is that virtual folders are not real folders and have no actual logical structure. Therefore, the content displayed in its body may actually be scattered in several real folders, and the virtual folder only serves as an induction and summary function.

Friends who have used e-mail should appreciate the charm of virtual folders-if friends only need to display all unread mail, the general method is to open each folder in which the mail is stored to see if there are unread mails in it. The e-mail box using the virtual folder technology contains a folder called "Unread Mail", which directly lists all unread mail. However, the difference from general folders is that virtual folders are not real folders and there is no actual folder.

Virtual folders provide a more convenient way for users to manage a batch of content-related files. All or all files according to the specific criteria required by the user are aggregated into a virtual folder. The files in the virtual folder are not limited to a physical location on the hard disk, but may be other forms. In fact, the files in the virtual folder may not even be stored on the hard disk. They can be content on a network share or custom application database, such as mail or other databases.

The file "cannot" be stored in a virtual folder, because that is essentially just a search query for file storage. There may be multiple situations when trying to store files to a virtual folder. Depending on the software implementation, the files may be redirected to a physical storage space.

Most implementations pre-index the files on the hard disk or a specific location to speed up the search, so that the index can be queried at the beginning of the search to quickly display and complete the search task, avoiding waiting for indexing and querying the entire folder structure. ^[1]

The virtual folder can be

BeOS Virtual folder BeOS

The first developer preview of this operating system was released in October 1995 and includes database-like features that make it easier for users to manage their files. For this feature, the file system indexes specific file attributes to help you quickly search. By default, the file system automatically indexes the file name, size, and last modification date, and can create indexes for other attributes when notified by other applications or users.

When the user performs a file search, a file is created in the folder "/ boot / home / queries", and the file name is derived from the query content and the date and time of the search, for example, "Name = Western Infirmary-Mar 21, 11:59: 40 PM. " The search query conditions are stored in an attribute called a "qrystr" file. When the file is opened, the file system queries the index and opens a tracking window to keep the latest list of files that match the criteria.

More search functions were added in subsequent releases. Release 2 introduced the ability to edit saved queries. Release 3 allows users to define the names of saved queries themselves. Prior to Release 4 in 1998, all queries were stored indefinitely. Beginning with R4, BeOS developers introduced a 7-day time limit for all queries. If users want to keep a query, they can unmark "Temporary" in the Find dialog. ^[2]

Mac OS X Virtual folder Mac OS X

Dominic Giampaolo, one of the leading developers of the BeOS file system, was involved in Apple's Mac OS X operating system and added a virtual folder system to it.

In April 2005, Apple released Mac OS X v10.4, which includes a virtual folder called " Smart Folders ". These folders are essentially dynamically updated by the Spotlight engine to contain content that matches specific criteria. For example, this can bring you a special folder containing all Word documents that contain the keyword "shpadoinkle" and have been edited in the last 7 days. Smart folders are created by saving a Spotlight search. Search conditions are recorded in a property list file with a .saveSearch suffix, which is saved by default in the "/ Users / username / Library / Saved Searches" folder.

A variant of the "smart folder" concept can be seen in many Spotlight engine applications, usually marked with a gear icon in purple tones. For example: smart mailboxes in messages and smart groups in contacts.

In earlier versions of Mac OS X without Spotlight, iApps (iTunes and iPhoto) had a similar concept, but they did not use a system-level Spotlight engine. ^[2]

Windows Virtual folder windows

In November 2006, Microsoft released Windows Vista, which allows users to save any search query as a "search folder", which is a type of virtual folder. Search folders are designed so that users don't need to remember where their files are stored. The search folder is not a physical folder, it is essentially an XML file that provides a defined query store for the Windows search subsystem. Because of this, search folders can be created anywhere a normal folder can be created. A similar method also exists in Windows XP. When the Windows Indexing Service is enabled, searches can be saved as .fnd files. However, the saved search query in Windows XP only saves the user's search criteria; the user still needs to specify the search location and perform the search again, and the search results are not presented dynamically.

Whenever you access the Search Folder, it returns results related to the saved search query; the actual list of files and folders is presented in the results list. The definition of a search query can be based on many parameters and attributes, including file name, specified date, the content of the file itself, related metadata, file type, file location, and various other attributes. A feature called a "query component" allows searchers to further segment results based on other "search folders."

Windows Vista, by default, references the profile of the user who originally created a saved search as part of the query's scope, which includes the disk partition. This design choice does not prevent saved searches from being shared with other users, but it prevents them from operating on different partitions or user profiles. Although the user can manually modify the content of the saved search to change the reference range to the% USERPROFILE% environment variable, which will enable it to operate on other machines or profiles regardless of the original author or location, Microsoft A "SearchMelt Creator" utility has been released that allows users to automate this process.

In earlier development versions of Windows Vista, these "search folders" that were pre-configured for default user configuration folders (such as documents, music, and pictures) replaced those folder links on the Windows Start menu. When browsing in Windows File Explorer, the navigation panel will dynamically populate the "Search Folder" related to the current viewing view; for example, when viewing the "Documents" folder, the navigation panel will be based on the author and keywords of the document , Type, and recently changed documents generate a Search Folder. These pre-release versions of the operating system also include other virtual folders, and searches are aggregated through the main "library" search folder. Microsoft stated that the goal of this approach is to go beyond the traditional physical folder concept, but the company's feedback shows that a large number of users are confused / confusing about the new approach. In particular, the "search folders" being put on the start menu led people to believe that they were multiple physical folders with similar names and contents.

Based on this feedback, the company decided to restore links to physical folders on the Start menu, similar to how they were displayed in previous versions of Windows, and removed several "search folders" that were available when Windows Vista was released to the manufacturer. Although less obvious on the interface, the operating system still contains several pre-configured search folders: recent documents, recent emails, recent music, recent pictures and videos, recent changes, and "Share with me" These are provided by an "index location" search folder that implements the early "library" concept.

In Windows 7, the concept of virtual folders was significantly implemented as a "library" feature. Like "Saved Search", "Library" is essentially just an XML file with the extension .library-ms. Its function is to collect a batch of files with specific attributes and display them on a familiar folder-style interface. The library has a namespace extension on File Explorer, and its XML files can be reused across Windows or the network. ^[2]

GNOME Virtual folder GNOME

In GNOME 2.14, the saved search is a virtual folder, the content is the search results of Nautilus, and the content comes from multiple backends. The contents of these folders are determined dynamically when the folder is opened, and are automatically updated when files are created or modified. ^[2]

Other implementations of virtual folders

Email client

Virtual folders are a common design structure for email clients. In early 1991, the Emacs-based mail reader VM provided a virtual folder design in its 5.09 version. VMs allow users to define virtual folders using rules, which can involve message content in one or more physical folders, and can be based on specific selection criteria, such as date, author, recipient, subject, message body, and more. Virtual folders can also be created based on previously defined virtual folders, so that the Evolution mail client created in 2000 by Helix Code can also be filtered based on criteria. Virtual folders are also included in the Evolution mail client. You can create folders and automatically list messages that match user-defined rules, such as listing all messages that involve specific addresses, or all messages that contain specific keywords. The new mail client (released in November 2002 and released in January 2003) provided by Opera web browser also provides virtual folders (called access points) for email management. Its virtual folder is automatically created based on active contacts, attachments, and assigned tags. Virtual folders are also created as a result of performing searches, and manual virtual folders can use multiple logical message headers for automatic classification (including using regular expressions). Microsoft Outlook 2003 added a similar feature called "Search Folders". In the first release of Gmail in 2004, all mail management was based on virtual folders implemented by "tags." Mozilla Thunderbird can also create search folders and allow searching multiple email accounts.

Music client

In July 2002, Apple announced that iTunes 3 offers a "smart playlist" feature, which can be considered a virtual folder. The only difference is that the search is not in the file system's folder structure, but in its internal storage area. Microsoft also added a similar feature to Windows Media Player 9 for Windows XP in 2003, called "AutoPlaylists." ^[2]