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Spotlight is a system-wide desktop search feature of Apple's OS X and iOS operating systems. Spotlight is a selection-based search system, which creates an index of all items and files on the system. It is designed to allow the user to quickly locate a wide variety of items on the computer, including documents, pictures, music, applications, and System Preferences. In addition, specific words in documents and in web pages in a web browser's history or bookmarks can be searched. It also allows the user to narrow down searches with creation dates, modification dates, sizes, types and other attributes. Spotlight also offers quick access to definitions from the built-in New Oxford American Dictionary and to calculator functionality. There are also command-line tools to perform functions such as Spotlight searches. Spotlight was first announced at the June 2004 Apple Worldwide Developers Conference, and then released with Mac OS X v10.4 in April 2005.〔 〕 A similar feature for iOS 3.0 with the same name was announced on March 17, 2009. ==OS X== Indices of filesystem metadata are maintained by the Metadata Server (which appears in the system as the mds daemon, or mdworker). The Metadata Server is started by launchd when Mac OS X boots and is activated by client requests or changes to the filesystems that it monitors. It is fed information about the files on a computer's hard disks by the mdimport daemon; it does not index removable media such as CDs or DVDs. Aside from basic information about each file like its name, size and timestamps, the mdimport daemon can also index the content of some files, when it has an Importer plug-in that tells it how the file content is formatted. Spotlight comes with importers for certain types of files, such as Microsoft Word, MP3, and PDF documents. Apple publishes APIs that allow developers to write Spotlight Importer plug-ins for their own file formats.〔 The first time that a user logs onto the operating system, Spotlight builds indexes of metadata about the files on the computer's hard disks.〔 It also builds indexes of files on devices such as external hard drives that are connected to the system. This initial indexing may take some time, but after this the indexes are updated continuously in the background as files are created or modified. If the system discovers that files on an external drive have been modified on a system running a version of Mac OS X older than 10.4, it will re-index the volume from scratch.〔 Within Mac OS X v10.4, Spotlight can be accessed from a number of places. Clicking on an icon in the top-right of the menu bar opens up a text field where a search query can be entered. Finder windows also have a text field in the top-right corner where a query can be entered, as do the standard load and save dialogue boxes. Both of these text fields immediately start listing results of the search as soon as the user starts typing in a search term, returning items that either match the term, or items that start with the term. The search results can be further refined by adding criteria in a Finder window such as "Created Today" or "Size Greater than 1 KB".〔 Mac OS X v10.4 and later also include command line utilities for querying or manipulating Spotlight. The mdimport command, as well as being used by the system itself to index information, can also be used by the user to import certain files that would otherwise be ignored or force files to be reimported. It is also designed to be used as a debugging tool for developers writing Importer plug-ins. mdfind allows the user to perform Spotlight queries from the command line, also allowing Spotlight queries to be included in things like shell scripts. mdls lists the indexed attributes for specific files, allowing the user to specify which files and/or which attributes. The indexes that Spotlight creates can be managed with mdutil, which can erase existing indexes causing them to be rebuilt if necessary or turn indexing off. These utilities are also available on Darwin. Although not widely advertised, Spotlight can perform boolean searches. By default if one includes more than one word, Spotlight performs the search as if an "AND" was included in between words. If one places a '|' between words, Spotlight performs an OR query. Placing a '-' before a word tells Spotlight to search for results that do not include that word (a NOT query). Currently Spotlight is unable to index and search NTFS volumes shared via SMB. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Spotlight (software)」の詳細全文を読む スポンサード リンク
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