File: file names. Full, short, long, correct and incorrect file name, its composition, template and mask. Saving a file in a different or older format. What is a file
Working with files and folders WINDOWS: the concept of a file, folder, saving, renaming
A file is a collection of data that has a name and is stored in the external memory of the computer (on a hard drive, floppy disk or CD). The file name consists of two parts: the base name and the extension (type), separated by a dot. WINDOWS does not impose such strict restrictions on the file name as DOS, but the extension consists of three characters and usually indicates which application created the file.
A directory is a file special type, containing information about other files (name, size, location, date and time of creation). At the same time, you can think of a directory as a place where files are located. The top directory - the root - on each disk is named after the corresponding disk. IN WINDOWS term"directory" has been replaced by an equivalent concept "folder". Many folders, with other folders with files nested within them, form a hierarchical “tree” structure. Each folder has a number of properties, the most important of which are: name, type, icon, size, creation date. The name can be up to 255 characters long.
The folder or file can be saved or copied. It is important to note that in order to save a file or folder, you must give it a unique name, since two files with the same name cannot exist. The name serves as an address, which means that there should not be two files on the computer that have the same name, however, if the files are in different folders, they may have same names, because full name file includes all the names of the directories that lead to it. This fully qualified file name is also called a file search path or file access path. Folders can be created on the disk, inside which files or other folders can be stored, called subfolders. Folder names are separated from each other and from the drive name using a backslash.
The file name, which must be unique, is supplemented by an extension - the format (type) of the file, which determines the nature (content) this file, in which program the file was created.
The file name structure is next view: name [.ext ], where name -unique name file, file extension, is optional, but its use is convenient for work, consisting of a maximum of three letters - a sign of optionality.
The file name consists of two parts, separated by a dot: the actual file name and the extension that determines its type (program, data, etc.). The actual name of the file is given by the user, and the file type is usually set automatically by the program when it is created.
Different operating systems have different filename formats. In the MS-DOS operating system, the file name itself must contain no more than eight letters of the Latin alphabet and numbers, and the extension consists of three Latin letters, for example: proba.txt
In the operating system Windows name the file can have up to 255 characters, and the use of the Russian alphabet is allowed, for example: Units of information.doc
Before the Windows 95 operating system appeared on most IBM computers PC worked operating room MS-DOS system, in which they acted very strict rules naming files. These rules are called convention 8.3
By convention 8.3, a file name can consist of two parts, separated by a dot. The first part can be up to 8 characters long, and the second part (after the period) can be up to 3 characters long. The second part after the dot is usually called the name extension.
When writing a file name, you are allowed to use only English letters and numbers. The name must begin with a letter. Spaces and punctuation are not allowed, except exclamation point(!), tilde (~) and underscore (_).
After the introduction of the Windows 95 operating system, file naming requirements became significantly more relaxed. They are also valid in all subsequent versions of Windows operating systems. 1. Up to 255 characters are allowed. 2. It is allowed to use symbols of national alphabets, in particular Russian. 3. Spaces and other previously prohibited characters are permitted, with the exception of the following nine: /\:*?"<>|. 4. You can use multiple periods in the file name. All characters after the last dot are considered a name extension.
The role of the file name extension is purely informational, not command-oriented. If you assign the extension TXT to a file with a picture, the contents of the file will not turn into text. It can be viewed in a program designed for working with texts, but such viewing will not give anything intelligible.
File system. Each storage medium (floppy, hard or laser disk) can store a large number of files. The order in which files are stored on the disk is determined by the installed file system.
Long file names have the following properties:
1. they can contain up to 255 characters, including extension;
2. they may contain spaces;
3. they can contain several dots (name extensions are those characters that follow the last dot);
4. they can contain any keyboard symbols except the following:
5. The length of the full file name, including its search path, cannot exceed 260 characters; therefore, it is not recommended to give too much long names folders;
6. It is undesirable to use spaces in the name, because Some programs do not work correctly with such files. It is recommended to replace spaces with underscores, for example: test_in_computer science_Asanov_Alexey.
Now imagine the complete picture of the file structure like this: the whole external memory computer is a cabinet with many drawers. Each box is an analogue of a disk; in the box there is a large folder (root directory); this folder contains many folders and documents (subdirectories and files), etc. The deepest nested folders contain only documents (files) or are empty.
The path to the file. To find a file in the hierarchical file structure It is extremely important to specify the path to the file. The path to the file includes the logical name of the disk, written through the "\" separator, and the sequence of names of nested directories, the last of which contains the given one. required file.
Full file name. The path to the file along with the file name is called the fully qualified file name. Example of a full file name: C:\Abstracts\Physics\Optical phenomena.doc C:\Abstracts\Informatics\Internet.doc C:\Abstracts\Informatics\Computer viruses.doc C:\Drawings\Sunset.jpg C:\Drawings\ Winter.jpg
In the operating room Windows system Instead of directories, the concept “folder” is used. Folder- a Windows object designed to combine files and other folders into groups. The concept of a folder is broader than the concept of a directory.
In Windows, at the top of the folder hierarchy is the Desktop folder. ( Next level represented by the folders My Computer, Trash and network(if the computer is connected to the local network).
There are a number of things you can do with files and folders: standard actions. Such actions with files as “create”, “save”, “close” can only be performed in application programs (“Notepad”, “Paint”, ...).
The actions “open”, “rename”, “move”, “copy”, “delete” can be performed in system environment. ‣‣‣ Copying (a copy of the file is placed in another directory);
‣‣‣ Moving (the file itself is moved to another directory);
‣‣‣ Deletion (the file entry is deleted from the directory);
‣‣‣ Renaming (file name changes).
Graphic Windows interface allows you to perform operations on files using the mouse using the Drag&Drop method (drag and drop). There are also specialized applications for working with files, so-called file managers.
Questions and tasks: 1. Write down the full names of all files
2. Build a directory tree C:\Drawings\Nature\Sky.bmp C:\Drawings\Nature\Snow.bmp C:\Drawings\Computer\Monitor.bmp C:\My Documents\Report.doc
9.5. Windows operating system
To replace the MS DOS operating system with its graphical Windows shells 3.1 and Windows 3.11 came full-fledged operating systems Windows family(first Windows 95, then Windows 98, Windows Millennium, Windows 2000, Windows XP, Windows Vista and Windows 7). The figure shows the stages of development of PC-class personal computers and the Windows operating system:
Operating systems family Windows is a 32-bit operating system that provides multitasking and multi-threaded application processing. Οʜᴎ supports convenient graphic user interface, ability to work in protected mode, compatibility with programs real mode And networking opportunities. Windows implements Plug and Play technology to support self-configuring hardware, allows long file names, and provides increased characteristics sustainability.
32-bit means that operations on 32-bit data are faster here than on 16-bit data. 32-bit Windows applications run in their own address space; access to ĸᴏᴛᴏᴩᴏᴇ is closed to other programs. This protects applications from each other's errors. If one application fails, the other continues to function normally. A failed application can be terminated.
Multitasking allows parallel work with multiple applications. While one of them is engaged, for example, in printing a document on a printer or receiving email from Internet networks, another might recalculate a spreadsheet or do other useful work.
Multithreading Allows specifically designed applications to simultaneously run multiple processes of their own. For example, when working with a multi-threaded spreadsheet, the user will be able to recalculate in one table while printing another and loading a third into memory. While one thread is waiting for, for example, the completion of a data exchange operation with a slow peripheral device, the other can continue to do his job.
Distinctive feature Windows is an object-oriented approach to system building. At the user level object approach is expressed in the fact that the interface is similar to real world, and working with the machine comes down to actions with familiar objects. Thus, folders can be opened, put in a briefcase, documents can be viewed, corrected, moved from one place to another, thrown into the trash, a fax or letter can be sent to the recipient, etc. The user works with tasks and applications in the same way as with documents on his desk. The object-oriented approach is implemented through the model desktop– primary Windows object. After Windows boot it is displayed on the screen. There are located on the desktop various objects: programs, folders with documents (texts, pictures, tables), shortcuts to programs or folders.
Shortcuts provide access to a program or document from multiple locations without creating multiple physical copies of the file. You can place not only application icons on the desktop individual documents, but also folders. Folders are another name for directories.
A significant innovation in Windows was task bar. Despite the small functionality, it makes the multitasking mechanism clearer and greatly speeds up the process of switching between applications. Externally, the taskbar is a strip, usually located at the bottom of the screen, which contains application buttons and the Start button. On the right side there is usually a clock and small icons of programs that are currently active.
Windows allows you to work with audio and video files various formats. A significant achievement of Windows was its built-in computer communications programs. Communication Windows tools are designed for ordinary users and do not require special knowledge. These facilities include the ability to work in local networks And global networks, setting up modems, connecting to e-mail and much more.
In the Windows operating system, the mouse is widely used when working with windows and applications. Typically the mouse is used to select text or graphic objects, checking and unchecking boxes, selecting menu commands, toolbar buttons, manipulating controls in dialogs, “scrolling” documents in windows.
In Windows, the right mouse button is also actively used. By placing the pointer over the object of interest and right-clicking, you can expand context menu, containing the most common commands applicable to this object.
When shutting down, you cannot simply turn off the computer without shutting down the system properly - this may lead to the loss of some unsaved data. To properly shut down, it is extremely important to save data in all applications that the user was working with, shut down all previously running DOS applications, open the “Start” button menu and select the “Shut Down” command.
Working with files and folders WINDOWS: the concept of a file, folder, saving, renaming - concept and types. Classification and features of the category "Working with files, folders WINDOWS: the concept of a file, folder, saving, renaming" 2017, 2018.
Note: Starting in February 2019, we'll begin adding new features for Office 365 for Windows and Mac users that make it easier to save files to the cloud. If you are logged into your account, then files will be saved to OneDrive by default. If you want to save your current files in a different location, select Extra options conservation to open the Save As window.
If you haven't received this update yet, saving in Office apps will work as before.
Advice:
File select team Save as.
Advice: Creating a template.
Select a folder from the list Recent folders Review.
Saving a copy as a new file (Save As)
Advice: if you are going to create new file based on an existing one, but save changes only in the new one; before making them, we recommend using the “Save As” command. Thus, original file will remain unchanged, and all changes will be saved in a new copy.
Press F12 or on the tab File select team Save as.
By default, Office saves a copy in the same location as the original file. If you want to save the copy to a different location, select it at this point. If the current location suits you, proceed to step 3.
The original file will close and you will continue working on a new copy of it.
Advice: If you frequently create new files from existing ones, you may find templates useful to make the process easier and more secure. additional information see the article Create a template.
Select a different location to save the file
If you save the file or a copy of it as described above, you can choose a different location.
Select cloud storage, website, or folder on your device where you want to save the file.
Select a folder from the list Recent folders, and if it doesn't show the location you want, click Review.
Saving a file in a different or older format
You can save the file in a different format so that it can be opened in another application or more early version application being used. For example, you might want to save Word document 2016 in RTF format, A Excel workbook- in CSV format.
Save a copy of the file or select a different location in Office 2013.
Select the cloud storage, website, or folder on your device where you want to save the file.
Select a folder from the list Recent folders, and if it doesn't show the location you want, click Review.
Saving a document navigation areas.
Saving a document
You can save the file in a different format so that it can be opened in another application or in an earlier version of the application you are using. For example, you might want to save a Word 2016 document in RTF format and an Excel workbook in CSV format.
File type dialog box Saving a document
Notes:
Open the tab File.
In field File name enter a new file name.
When using the dialog box Saving a document You can also save the file to a new location using navigation areas.
IN address bar select or specify the folder path.
For quick view frequently used folders, use the navigation pane.
Click the arrow button to display other file types.
Additionally, using the dialog box Saving a document you can rename the file or change its location by selecting a different folder.
You can save the file in a different format so that it can be opened in another application or in an earlier version of the application you are using. For example, you might want to save a Word 2016 document in RTF format and an Excel workbook in CSV format.
If you're using Office 2010, you can save files in previous formats Office versions by selecting a version from the list File type dialog box Saving a document. For example, a Word 2010 (DOCX) document can be saved in the 97-2003 (DOC) format.
Notes:
Saving information Microsoft Access 2010 ACCDB files in the older MDB format, see Converting an .accdb database to an older format.
Default files in applications Microsoft Office are saved in the default working folder. To save a copy in a different location, select a different folder from the list.
Saving a document in Windows 7 and Windows Vista
1. In the address bar, select or specify the path to the folder.
2. To quickly view frequently used folders, use the navigation pane.
Saving a document V Microsoft Windows XP
You can also save the file to a new location using the list Folder or in locations saved in the panel My addresses.
1. Select a folder from the Folder list.
2. To quickly view frequently used folders, use the "My Addresses" panel.
3. Click the arrow button to display other file types.
To save a copy in a different folder, follow the steps above, but select a different drive from the list Save to or another folder in the folder list. To save a file to new folder, press the button Create a folder .
Usage automatic recovery does not eliminate the need to regularly save files. If the recovered file is not saved after opening, it will be deleted and any unsaved changes will be lost. When saved, the restored file replaces the original file unless you give it a new name. The more often you save files, the more data you can recover if there is a power outage or other problems occur while working with the file.
See the steps that correspond to the one you are using. Office product 2007.
Word 2007
Excel 2007
InfoPath 2007
On the menu Service click the button Options and open the tab Additionally.
Check the box Save data when filling out forms automatic saving every.
In field min.
PowerPoint 2007
Project 2007
On the menu Service click the button Options and open the tab Additionally.
Check the box Save every.
In field min. Enter or select the desired file saving interval.
Publisher 2007
On the menu Service click the button Options and open the tab Additionally.
Check the box Autosave every.
In field min. Enter or select the desired file saving interval.
Visio 2007
On the menu Service select team Options and open the tab Saving and Opening.
Check the box Autosave every.
In field min. Enter or select the desired file saving interval.
Additionally. To specify a search, use templates for a group of files - * and?. With * the user is not specified by the number of characters in the file name, but with? it must be repeated as many times as there are letters in the file name. To speed up the search for a document, you can include a line of text or select the Date tab and clarify during what time the files were created (Fig. 14).
What is the WISIWIG principle ?
GUI Windows is based on WYSIWYG principle(What You See Is What You Get - what you see is what you get). This principle means that the image of a document on the screen when viewing and editing it and the image of the document on paper when printing it are practically the same.
What are file attributes, list them. How are they installed and removed?
Currently file systems, FAT32 and NTFS, the following file attributes can be distinguished:
“Read-only” means that the file is read-only by the operating system, i.e. no corrections can be made to it. In most cases, this does not mean that it is impossible to make corrections at all, just that if an attempt is made to change a file with this attribute, the user will be shown a corresponding warning.
“Hidden” - it means that a file with this attribute is not displayed when displaying certain lists of files. Most programs can customize how this attribute is processed. For example, the standard Windows XP Explorer allows you to both hide and show files with the “hidden” attribute. In the second case, the file icon appears translucent.
“System” - files with the “system” attribute most often refer to critical operating system files that cannot be deleted or modified. In general, the "system" attribute is a "weighted" version of the "read-only" attribute combined with the "hidden" attribute. In the standard Windows XP Explorer, the “system” attribute is processed similarly to the “hidden” attribute - such files are hidden from the user by default, but you can allow them to be shown.
“Archive” - currently, for its intended purpose, this FAT file attribute is practically not used. This attribute was originally intended to indicate to archiving programs the files intended for Reserve copy. In other words, a program backing up a file on a hard drive had to reset the “archive” attribute, and programs that subsequently made any changes to this file, on the contrary, had to set it again. Thus, the backup program by checking this file attribute could easily determine whether a given file on the hard drive has changed since the previous backup.
How to set or uncheck an attribute: Right-click on the file, select the “General” tab (usually it is the default) and at the bottom of the window we see attributes, you can check or uncheck them, after changing the file parameters, click the “Apply” button and close window.
Name the extensions of text documents, documents M that you know S - OFFICE , graphic files.
Extension- these are several letters or numbers located after the dot in the file name.
Extension File Type Example
doc,docxdocuments(MicrosoftWord) Letter.doc
xlstables(MicrosoftExcel) Catalog.xls
txttext documents text.txt
pptpresentations (MicrosoftPowerPoint) Presentation.ppt
bmp drawing, photo Figure.bmp
jpg drawing, photograph Photo.jpg
tif drawing, photo Nature.tif
gif drawing, photograph Drawing.gif
The difference between the Save File command and the Save As... command is that the Save As... command prompts you for the file name and allows you to change the file format or location. The Save command simply saves the file in its current location.
File name Name 255 Up to 255 characters, Latin letters of the Latin and Russian alphabet. Must not contain the characters: / \ : * ? | Extension Three letters of the Latin alphabet. Separated from the name by a dot. Automatically set by the program and indicates the file type.
Some file types and their extensions Executable – files containing ready-to-execute comexe programs File typesExtension Text documents txtdocrtf Graphics – files containing images bmpjpggif Sound – files containing voices and music wavmid
PROGRAMS AND DATA Executable files Text files Graphic files Sound files Files containing ready-to-execute programs Files containing text Files containing images Files containing voices and music comexe doc txtrtf jpg bmp gif wav mid
File Windows uses the principle that any collection of disk data is assigned a name. Specific area a disk that has its own name is called a file. To run a program, you open an icon on the screen associated with the program file. Edited new document using a text editor, you save it on disk under a certain name - this will create a new file, and somewhere on the screen a new icon corresponding to it will appear.
File name The file name in Windows can be typed in both Russian and with Latin letters, but no more than 255 characters. Each file has a three-letter extension that serves as a description of the file type for the operating system. The user should under no circumstances change file extensions. Files cannot have the following extensions: PRN, LPT1, LPT2, LPT3, AUX, COM1, COM2, COM3, COM4, CON, NUL, CLOCK$ with any extensions, because the operating system reserves all these names to designate input/output devices, this allows you to work with them as files.
File name (continued) Data files used by various application programs, also often have traditional extensions. Let's list some of them: DOC - document files of a word processing program ( word processor) Word Microsoft. RTF - documents in universal format Rich Text Format from Microsoft. XLS- Spreadsheets Excel package from Microsoft. TIF - files containing graphic images V TIFF format, widely used for storage graphic information. BAK- backups, saved by many insurance programs.
Directory To organize files on disk, they are placed in different folders, or, which is the same, directories. In order to open a folder, like any object, you need to double-click on its icon or press the Enter key on it. Opened folder is a regular window: with a menu, toolbar and other necessary accessories. You can open any object in a folder window double click mouse over it, the folder menu command (File / open) or by pressing Enter keys. Depending on the menu settings (View / Options), the subfolder will either open in a new window or occupy the current window.
Catalog (continued) To move to more high level folders, you should press Backspace or the button to move up one level on the toolbar of the folder window or Explorer. The drop-down list on the toolbar is convenient for moving up and down.
Catalog (continued) Available information about the current (selected by the cursor) object or selected objects is reflected in the status bar at the bottom of the window. To select an object, you need to click on it with the mouse; to select a group of objects, you need to “circle” them with the mouse. To select objects randomly, you need to hold down Ctrl. If you try to select the object again, the selection is removed.
Working with objects Any operations related to transferring object icons are best performed with the right mouse button. When you release the right button, a context menu similar to this will appear. Now you can choose required action or refuse the operation by clicking on any place on the desktop, past context menu.
Copying objects First method: Drag selected objects into the target directory window while holding the right mouse button. You can drag them to the target directory button on the taskbar and wait for its window to open. Release the mouse button and select the Copy command from the menu that appears.
Copying objects (continued) Second method: While holding Ctrl, drag the selected objects into the window (or drag them to the button) of the target directory with the left mouse button. Third method: If the source and destination folders are on different drives, you can drag objects with the left mouse button (without holding Ctrl).
Transferring objects First method: Drag selected objects into the target directory window while holding the right mouse button. You can drag them to the button on the taskbar and wait. Until his window opens. Release the mouse button and select the Move command from the menu that appears.
Transferring objects (continued) Second method: While holding Shift, drag the selected objects into the window (or drag them to the button) of the target directory with the left mouse button. Third method: If the source and destination folders are on the same drive, you can drag objects with the left mouse button (without holding Shift).
Deleting objects Select the menu of the folder or Explorer window (File / Delete), or the context menu item of the selected objects Delete (delete), or click Del button. Confirm the delete operation in the dialog box that appears. Drag the selected objects to the Trash with the left mouse button.
Creating object shortcuts Drag the object to the location where you want to create the shortcut while holding the right mouse button. From the context menu, select the Create shortcut command. Drag the object to the location where the shortcut is created with the left mouse button while holding Ctrl+Shift. Be careful - if you copy or delete shortcuts, it will be the shortcuts that will be copied or deleted, not the parent objects.
Renaming objects To rename an object, select it, select the Rename command from the folder window or Explorer menu, or click the label of the selected object. After this, you can simply edit the signature. You cannot rename multiple objects at once.
Questions: What name can the file have? What is the file format (extension)? What does the concept of saving a file mean? What name can a directory (folder) have? As you understand Windows principle“Point and click?” What is the point of highlighting an object? Give examples from Everyday life, which also use the principle of selection. Working in which editor can you create a “File.DOC” file? You have created a file called "File.DOC", placed it in the "My Documents" folder, and placed a shortcut for this file on your desktop. How to delete this file? How can I rename this file (see previous question)? How can I copy this file to the “10th grade” folder if it is located on the same disk?
Since address data also has a size and must also be stored, storing data in small units such as bytes is inconvenient. They are also inconvenient to store in larger units (kilobytes, megabytes, etc.), since incomplete filling of one storage unit leads to storage inefficiency.
Storing and retrieving information on external storage devices is important. External storage devices are a kind of informationtion warehouses, where programs and data are stored for a long time until they are needed to solve a problem. Now imagine that goods are stored in a warehouse without any system. The larger the warehouse, the more difficult it is to find the right product. Or take, for example, a closet in which various documents, books, reports, certificates, etc. In the absence of a specific storage organization, search necessary documents, especially if their number is significant, it can be very challenging task, requiring a lot of time.
The unit of data storage is a variable-length object called a file.
File is a named collection of data that has a certain internal organization and occupies a certain area of the information carrier.
Usually in separate file store data belonging to the same type. In this case, the data type determines file type.
Since there is no size limit in the definition of a file, you can imagine a file having 0 bytes (an empty file) and a file having any number of bytes.
The file name must be unique - without this it is impossible to guarantee unambiguous access to data. In means computer technology the requirement of name uniqueness is ensured automatically - neither the user nor the automation can create a file with a name identical to an existing one.
The file may contain: a program in machine codes, program text in an algorithmic language, document text, report, salary slip, article, numerical data, recording of human speech or musical melody, drawing, illustration, drawing, photograph, video, etc.
The file is created at the user's direction or automatically, using various software systems, such as operating systems, shells, programming tools, etc. A certain name is assigned to the created file, space is allocated to it on disk media, and it in a certain way registered in the operating system. The newly created file can be filled with some information.
Each file has a number of characteristic properties - attributes. The most important attributes of the file are:
ü name,
ü expansion,
ü time and date of creation.
File name, just like the name of a person, the name of a document, a book, serves to be able to distinguish one file from another, to point to the desired file. In various operating systems, file names are formed according to different rules. For example, in the MS DOS operating system, the file name is
ü sequence of letters of the Latin alphabet,
ü some special characters (~, _, -, $, &, @, %,",!,(>)> (>). #).
The name can contain from one to eight (1 ... 8) characters and is selected randomly. It is advisable to select file names so that the user can easily remember what exactly is stored in this file. For example, a file containing a report for the 4th quarter can be called otchet4, a file with a salary slip can be called vedzarpl, and a file with a picture can be called picture.
In the MS DOS operating system, the file name cannot contain
ü spaces,
ü letters of the Russian alphabet,
In addition, it cannot contain more than eight characters. Generally speaking, this is enough significant restrictions. For example, a file containing a company’s report for the 4th quarter, which we called otchet4, would preferably be called “Report for the 4th quarter”, in extreme cases “Otchet za 4 kvartal”, using the so-called transliteration , when words of one language are written with letters of another. In operating rooms Unix systems and Windows 9.x, restrictions on the length of the name, the use of spaces and periods in the name have been removed. And in the Windows 9.x operating system, in addition, you can use Russian letters in the name. Thus, a file in Unix may be named “Report za 4 kvartal”, and in Windows 9.x the name “Report for the 4th quarter” is also allowed.
In addition to the name, each file may or may not have extension. The extension is used to characterize the contents of the file in a certain way. For example, the doc and txt extensions indicate that the file contains some kind of document or text, and bmp extension has a file containing an image in bitmap format. The extension, if any, is separated from the file name by a dot. In the MS DOS operating system, the extension can contain from one to three characters, for example, otchet4.doc, vedzarpl.txt, picture.bmp, and in Unix and Windows 9.x systems more than three characters are allowed. If there is no extension, then there is no dot in the file name.
If a file is created using any software system, then, as a rule, it automatically receives a standard extension for this system, and the user only needs to select or specify the name. Subsequently using standard extensions software system recognizes “its” files. Operating systems provide whole line standard extensions(Table 3.1).
Table 3.1
Some MS DOS and Windows 9.x extensions
| Extension | File contents |
| A type of program in machine code (executable file) |
|
| Command file (executable file) |
|
| File program documentation or document file |
|
| File with text |
|
| Numerical data file |
|
| Help file, that is, a built-in file help system |
|
| Device Driver |
|
| Temporary or working file |
|
| Type of graphics file |
Files with the extension .com (common) and .exe (execute) contain programs machine language. These files are often called program files. The differences between com files and exe files relate to their internal organization. These differences do not affect the way files are handled in any way. Files with the extension .bat (batch) contain arbitrary sequences of operating system commands. Such files are usually called batch files. The term « executable file" combines the concepts " program file" And " batch file" In other words, an "executable file" means that the file contains either a machine language program that can be directly executed by the computer's processor (files with the .exe and .com extensions) or a sequence of operating system commands (the .bat file) that are also executed, but only by accessing the appropriate programs and operating system tools.
An important attribute file is his length. The file length is equal to the amount of space the file occupies on disk or tape and is therefore measured in bytes. The value of this attribute is used to determine whether the file can be placed on a free space disk media and for some other purposes.
When a file is initially written to disk, and when changes are made to the file using the system clock ( special program, included in the operating system) automatically records the time and date the file was written to the disk device. Date and time attributes are used to identify the most recent versions of a file.
In addition to the considered basic file attributes in the MS operating system DOS files have four more attributes - read-only, system, hidden and archive. Each of these attributes has exactly two states - the attribute is on or the attribute is off.
Enabling the read-only attribute means that the file cannot be modified in any way. In addition, the destruction of such a file is complicated. The system attribute is usually enabled only for the main operating system files. The hidden attribute is enabled for those files that, when viewing the list of files located on disk device, operating system commands are not included in this list.
Operating systems provide a way to make collective actions with files easier. The action that needs to be performed on a group of files is specified only once, but along with the action, not the full name of a single file is specified, but a special name that allows the operating system to recognize all the files in the group and then perform the desired action on them. This name is called a wildcard name, pattern, or mask. The group name of files is formed using the characters “*” and “?”.
The symbol * found in a group name is interpreted operating system as "any sequence of any title characters." Thus, the group name a* corresponds to any names starting with the letter “a”: a1, azbuka, a2z4.
Symbol? is perceived by the OS as any single character, that is, it corresponds to exactly one arbitrary name character. For example, the pattern otchet?.doc matches any names with the extension .doc, in the name of which the name segment otchet is followed by exactly one character, for example, otchet1.doc, otchet4.doc, otchet%.doc, otchet#.doc, etc.
A few more examples:
Txt – files with any two-letter names and extension .txt;
*.bak – files with any names and extension .bak;
prog1.* – files with the name progl and any extension;
*.* – files with any names and any extensions.
