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  1. 1. MS-DOS
  2. 2. Computer Files <ul><li>In an organization, various files are maintained like employee file, client file or purchase file etc. </li></ul><ul><li>Similarly, a computer hard disk contains various files such as textual file, graphics file etc. </li></ul><ul><li>Every file is given certain appropriate names. </li></ul>
  3. 3. Continued… <ul><li>A file name should be descriptive and meaningful. </li></ul><ul><li>A file name can have two parts: </li></ul><ul><li>Primary name </li></ul><ul><li>Extension </li></ul><ul><li>And generally they are separated with the help of a dot. </li></ul>
  4. 4. Continued… <ul><li>A primary name can have a maximum of eight characters while an extension can have maximum of three characters. </li></ul><ul><li>A file name is valid even without an extension. </li></ul><ul><li>Extensions help in identification of files. </li></ul><ul><li>File names should be valid. </li></ul>
  5. 5. MS-DOS/PC-DOS/DOS <ul><li>It is non graphical, line-oriented command-driven operating system having simple interface and non friendly environment. </li></ul><ul><li>User can type the commands either in upper case or in lower case but DOS interprets/stores everything in upper case letters. </li></ul>
  6. 6. Continued… <ul><li>If you boot the system from hard disk drive by default the prompt that you find in DOS looks like </li></ul><ul><li>C:> </li></ul><ul><li>If you are booting from floppy drive then prompt will look like </li></ul><ul><li>A:> or B:> </li></ul><ul><li>If you are booting from optical disk drive or CD then prompt will look like </li></ul><ul><li>E:> </li></ul>
  7. 7. Let’s define DOS now <ul><ul><li>It is an interpreter, that provides a linkage(interface) between electronic circuitry and program. </li></ul></ul><ul><ul><li>It is a program loaded into the memory of user’s PC before execution of any application. </li></ul></ul><ul><ul><li>It creates an environment for managing the resources and execution of any program having extension .exe,.com,.bat </li></ul></ul>
  8. 8. More about DOS <ul><li>It is a single user operating system </li></ul><ul><li>The core of DOS is contained in three files, IO.SYS, MSDOS.SYS and COMMAND.COM </li></ul><ul><li>The disk that contains all the three files is called a Bootable disk or Startup disk or simply DOD disk. </li></ul>
  9. 9. Bootstrap procedure <ul><li>After the system unit is switched on , a search is made on A drive for DOS software, if it is not available it is searched on the hard disk. Then it is loaded automatically. </li></ul>
  10. 10. Important Note <ul><li>A floppy disk or hard disk is divided into concentric circles called tracks. These tracks are further sub divided into sectors. The boot sector is the first sector on the disk. </li></ul>
  11. 11. <ul><li>IO.SYS </li></ul><ul><li>MSDOS.SYS </li></ul><ul><li>COMMAND.COM </li></ul>
  12. 12. IO.SYS <ul><li>It has two main parts: </li></ul><ul><li>-To verify the various input and the output devices. All drivers together called DISK BIOS. </li></ul><ul><li>-Another part is SYS.INI which loads the file MSDOS.SYS from hard disk into memory and it becomes a memory resident program. </li></ul>
  13. 13. MSDOS.SYS <ul><li>Provides a link between BIOS and user’s application program. </li></ul><ul><li>Provides the facility of isolating the program from the physical aspect of the system and intricacies of the hardware </li></ul>
  14. 14. Continued… <ul><li>It provides the following functions: </li></ul><ul><li>-Process Control </li></ul><ul><li>-Memory Management </li></ul><ul><li>-Application Program Interface </li></ul><ul><li>-File management System </li></ul>
  15. 15. COMMAND.COM <ul><li>It is divided into two portions: </li></ul><ul><li>-Resident portion </li></ul><ul><li>-Transient portion </li></ul>
  16. 16. DOS commands <ul><li>DOS commands are divided into two parts: </li></ul><ul><li>Internal Commands </li></ul><ul><li>External Commands </li></ul>
  17. 17. Internal Commands <ul><li>These commands are automatically loaded in the memory when DOS is loaded in the memory. </li></ul><ul><li>These commands cannot be seen with the help of DIR command. </li></ul><ul><li>They are easy to learn and operate. </li></ul>
  18. 18. Continued… <ul><li>CLS </li></ul><ul><li>DIR </li></ul><ul><li>DATE </li></ul><ul><li>TIME </li></ul><ul><li>VOL </li></ul><ul><li>VER </li></ul><ul><li>COPY CON </li></ul><ul><li>TYPE </li></ul><ul><li>MD </li></ul><ul><li>CD </li></ul><ul><li>RD </li></ul><ul><li>PATH </li></ul><ul><li>COPY </li></ul><ul><li>PROMPT </li></ul><ul><li>REN </li></ul><ul><li>DEL </li></ul>
  19. 19. Continued… <ul><li>CLS – To clear the display screen </li></ul><ul><li>C:>CLS </li></ul><ul><li>DIR – To display list of directories, sub directories and files. </li></ul><ul><li>C:>DIR </li></ul><ul><li>DATE – To display the system’s current date and new date can be entered. </li></ul><ul><li> C:>DATE </li></ul>
  20. 20. Continued… <ul><li>TIME – To display the current system’s time and new time can be entered. </li></ul><ul><li> C:>TIME </li></ul><ul><li>VOL – To display the volume label or name of the volume given by the user to a disk and to check the volume name given by the label or format command. </li></ul><ul><li> C:>VOL </li></ul>
  21. 21. Continued… <ul><li>VER – Displays the current/installed version of DOS on the system. </li></ul><ul><li> C:>VER </li></ul><ul><li>COPY CON – To create the file. </li></ul><ul><li> C:>COPY CON Table </li></ul><ul><li>^Z </li></ul><ul><li>1 file(s) copied </li></ul>
  22. 22. Continued… <ul><li>TYPE – To display the contents of the file. </li></ul><ul><li> C:>TYPE </li></ul><ul><li>REN – To rename old file name with new file name. </li></ul><ul><li> C:>REN abc xyz </li></ul><ul><li>DEL-To delete the single file,multiple files can be deleted by using wild cards. </li></ul><ul><li> C:>DEL table.exe </li></ul><ul><li> C:>DEL *.* </li></ul>
  23. 23. Continued… <ul><li>MD – to create a directory or sub directory under the current directory. </li></ul><ul><li> C:>MD fan </li></ul><ul><li>CD – to change from one directory or sub directory to another directory or sub directory. </li></ul><ul><li> C:>CD.. </li></ul><ul><li> C:>CD fan </li></ul><ul><li>RD – to remove a directory or sub directory and it should be empty before deleting it. </li></ul><ul><li> C:>RD fan </li></ul>
  24. 24. Continued… <ul><li>PATH- To provide access to the files located in other directory paths or disk. </li></ul><ul><li> C:>PATH=D:AC; </li></ul><ul><li>COPY-To copy one or more files to another disk with same filename. </li></ul><ul><li> C:>COPY E:*.* D:AC </li></ul>
  25. 25. External Commands <ul><li>These are not the permanent part of the memory. </li></ul><ul><li>To run these commands , external files are required. </li></ul><ul><li>These are used for relatively complex jobs like copying an entire diskette into another, sorting a disk etc. </li></ul>
  26. 26. Continued… <ul><li>EDIT </li></ul><ul><li>ATTRIB </li></ul><ul><li>BACKUP </li></ul><ul><li>RESTORE </li></ul><ul><li>CHKDSK </li></ul><ul><li>DISKCOPY </li></ul><ul><li>DISKCOMP </li></ul><ul><li>DELTREE </li></ul><ul><li>DOSKEY </li></ul><ul><li>FORMAT </li></ul><ul><li>FDISK </li></ul><ul><li>FIND </li></ul><ul><li>LABEL </li></ul><ul><li>MORE </li></ul><ul><li>MODE </li></ul><ul><li>MOVE </li></ul><ul><li>PRINT </li></ul><ul><li>SCANDISK </li></ul><ul><li>SORT </li></ul><ul><li>SYS </li></ul><ul><li>TREE </li></ul><ul><li>POWER </li></ul>
  27. 27. Continued… <ul><li>Edit- </li></ul><ul><li>-To execute EDIT.COM is required. </li></ul><ul><li>-This file utilizes 413KB space of memory. </li></ul><ul><li>-Edit program is a full screen editor. </li></ul><ul><li>-Purpose is to create a new file or modify the contents of an existing file. </li></ul><ul><li>- Syntax is C:>EDIT filename.extension </li></ul>
  28. 28. ATTRIB <ul><li>ATTRIB: </li></ul><ul><li>To execute ATTRIB.EXE file is required </li></ul><ul><li>Utilizes 11,208 KB space in memory. </li></ul><ul><li>Purpose is to change the attribute of a file. </li></ul><ul><li>Syntax is C:>ATTRIB filename </li></ul><ul><li> C:>ATTRIB fan +H+R </li></ul>
  29. 29. Attributes <ul><li>Attributes </li></ul><ul><li>+R - Read only </li></ul><ul><li>-R - To remove read only </li></ul><ul><li>+H - To hide the file </li></ul><ul><li>-H - To unhide a hidden file </li></ul><ul><li>+A - To set the file Archival </li></ul><ul><li>-A - To reset the file Archival </li></ul><ul><li>+S - To set the system file </li></ul><ul><li>-S - To reset for system file </li></ul>
  30. 30. Backup Command <ul><li>Back Up </li></ul><ul><li>Used to copy the various files from the hard disk or floppy to create backup disk. </li></ul><ul><li>The file required is BACKUP.EXE </li></ul><ul><li>Covers 35,715 KB for its storage </li></ul><ul><li>Syntax is C:>BACKUP Source path options Target path </li></ul>
  31. 31. Options <ul><li>/S – to copy all subdirectories of source path </li></ul><ul><li>/M – to copy all files of source path which are modified since last backup. </li></ul><ul><li>/A – to copy files to the target disk without erasing the target disk. Without this option Backup command erases all files of target disk. </li></ul><ul><li>/D - to copy files saved on or after given date </li></ul><ul><li>/T – to copy files saved on or after given time. </li></ul><ul><li>/F – to format the target disk before doing backup. </li></ul><ul><li>/L - Creates a file containing time and date of backup files. </li></ul><ul><li>C:>BACKUP C:DOS A:/S/L </li></ul>
  32. 32. Restore <ul><li>Used to restore files copied by backup command. </li></ul><ul><li>File required for this command is RESTORE.EXE. </li></ul><ul><li>Space required for this is 38342 Bytes. </li></ul><ul><li>Syntax is C:>Restore Source path Options Target path </li></ul>
  33. 33. Options <ul><li>/S – to restore all files from all subdirectories. </li></ul><ul><li>/P – to prompt before restoring files that are read only and which are changed since the last backup. </li></ul><ul><li>/B - to restore all files on or before the given date. </li></ul><ul><li>/A - to restore all files on or after the given date. </li></ul><ul><li>/E – to restore files on or earlier than given time </li></ul><ul><li>/L – to restore files on or later than given time. </li></ul><ul><li>/N - to restore files that are no longer exists on destination disk. </li></ul><ul><li>/D – to restore files which match given specification on the backup disk. </li></ul><ul><li>Example:- C:>RESTORE B: C:/S </li></ul>
  34. 34. CHKDSK <ul><li>Requires CHKDSK.EXE file </li></ul><ul><li>Takes 12,241bytes for storage. </li></ul><ul><li>Returns the configuration status of the selected disk. </li></ul><ul><li>Returns volume serial number, total disk space, space in hidden files, space in directories, space in user files, space available on disk, number of bytes in each allocation unit, total number of allocation units, available number of allocation units, total memory and free memory. </li></ul><ul><li>Syntax is C:>CHKDSK drive name </li></ul>
  35. 35. DISKCOPY <ul><li>Requires DISKCOPY.COM file. </li></ul><ul><li>Uses 13,335 bytes of storage. </li></ul><ul><li>Used to make duplicate copy of the disk like xerox copy. It formats the target disk and then copies the files by collecting files from the source disk and copies to the target disk </li></ul><ul><li>Syntax is C:>diskcopy <source path> <destination Path> </li></ul>
  36. 36. DISKCOMP <ul><li>Requires DISKCOMP. COM file </li></ul><ul><li>Covers 10748 bytes of storage </li></ul><ul><li>To compare the disks </li></ul><ul><li>To find out they are identical or not </li></ul><ul><li>If we will try to compare two dissimilar disk it will display an error message. </li></ul><ul><li>Syntax is: C:> DISKCOMP <<source disk path>> <<target disk path>> </li></ul>
  37. 37. DELTREE <ul><li>Requires DELTREE.EXE file </li></ul><ul><li>Space required is 11111 bytes </li></ul><ul><li>Use to delete files and directories </li></ul><ul><li>Syntax is C:> DELTREE <Path> </li></ul>
  38. 38. FIND <ul><li>Requires FIND.EXE </li></ul><ul><li>Takes 6770 bytes for its storage </li></ul><ul><li>Use to search files stored on the disk and data stored in the files </li></ul><ul><li>Syntax is C:> Find “text” <filename> </li></ul><ul><li>C:> DIR|FIND “filename” </li></ul><ul><li>/C- returns number of lines containing specified text </li></ul><ul><li>/I- ignores upper case and lower case </li></ul><ul><li>/N- displays number of lines that contains the specified text </li></ul>
  39. 39. LABEL <ul><li>Requires LABEL.EXE </li></ul><ul><li>9390 bytes for its storage </li></ul><ul><li>Used to see volume label and to change volume label </li></ul><ul><li>The label should be maximum of 11 characters. </li></ul><ul><li>Syntax is C:> Label <Drive Name> </li></ul>
  40. 40. Print <ul><li>Required PRINT.EXE file and 15656 bytes for storage </li></ul><ul><li>Used to print the files </li></ul><ul><li>Files must be standard text files and containing data compatible to the printer. </li></ul><ul><li>Syntax is C:> PRINT <Filename> </li></ul>
  41. 41. DOSKEY <ul><li>Requires DOSKEY.COM </li></ul><ul><li>It takes 5861 bytes of storage media </li></ul><ul><li>Used to display the history of the DOS commands typed by user using the keyboard. </li></ul><ul><li>It stores number of commands in memory buffer according to its size. </li></ul>
  42. 42. Format <ul><li>Requires FORMAT.COM </li></ul><ul><li>Requires 22974 bytes </li></ul><ul><li>Use to make disk usable for operating system by dividing the disk into magnetic tracks and sectors </li></ul><ul><li>Number of sectors and tracks depends upon capacity of the disk and dos version </li></ul><ul><li>Syntax is C:> format <drivename> </li></ul>
  43. 43. FDisk <ul><li>Requires FDISK.EXE and requires 29336 bytes </li></ul><ul><li>It is used to make a fixed disk for use </li></ul><ul><li>To make partition of high capacity fixed disk and can organise cylinder on it to store the data </li></ul><ul><li>Syntax is C:> FDISK </li></ul>
  44. 44. More <ul><li>Requires MORE.COM file and 2545 bytes for storage </li></ul><ul><li>It is a filter command like find and sort, to see the contents of the file page by page </li></ul><ul><li>Used with dir and type command </li></ul><ul><li>Syntax is C:> More <file name> </li></ul><ul><li>C:> Type <filename>|more </li></ul>