1. Input - Output

2. Files API
Files are too managed with the help of handles. When handle is set it is possible to use it in input/output operations
That goes for all I/O operations

3. CreateFile Returns file handle? What about: streams disks
communications
pipes
etc?

5. lpFileName – file name
dwDesiredAccess – generic access rights
dwShareMode – sharing mode
lpSecurityAttributes – inheritant rights
dwCreationDisposition – creation mode
dwFlagsAndAttributes – flags and attributes
hTemplateFile – template handle

6. dwDesiredAccess Shows what can be done with file: GENERIC_READ
GENERIC_WRITE
GENERIC_EXECUTE
GENERIC_ALL

7. dwShareMode Sharing mode of the file or device:
0 – file cannot be shared until handle is closed
FILE_SHARE_READ
FILE_SHARE_WRITE
FILE_SHARE_DELETE

8. lpSecurityAttributes – saugumo požymis
Protects against unwanted access
NULL – handle cannot be inherited by child processes
Pointer to SECURITY_ATTRIBUTES
pointer to SECURITY_DESCRIPTOR
recommended not to modify structure directly

9. dwCreationDisposition
Action to take:
CREATE_ALWAYS
CREATE_NEW
OPEN_ALWAYS
OPEN_EXISTING
TRUNCATE_EXISTING
requires GENERIC_WRITE

10. dwFlagsAndAttributes
File or device flags and attributes.
Some flags and attributes apply to files only
0 – device is not a file
Other most common flags and attributes:
FILE_ATTRIBUTE_NORMAL
FILE_ATTRIBUTE_HIDDEN
FILE_ATTRIBUTE_READONLY
FILE_ATTRIBUTE_ARCHIVE

11. hTemplateFile GENERIC_READ
Supplies file attributes for file being created
NULL – if not used
Ignored when opening existing file

12. CreateFile2

13. ReadFile

14. ReadFileEx

15. Overlapped I/O Asynchronous I/O Complexity OVERLAPPED structure
FileIOCompletionRoutine callback function

18. WriteFile

19. WriteFileEx

20. File attributes (GetFileAttributes)
Commonly used attributes:
FILE_ATTRIBUTE_ARCHIVE
FILE_ATTRIBUTE_HIDDEN
FILE_ATTRIBUTE_NORMAL
FILE_ATTRIBUTE_READONLY
FILE_ATTRIBUTE_SYSTEM

21. CopyFile lpExistingFileName – name of an existing file
lpNewFileName – name of new file
bFailIfExists – if TRUE existing file will not be overwritten

22. CopyFile2

23. CopyFileEx (1)

24. CopyFileEx (2)
lpProgressRoutine – callback function (CopyProgressRoutine)
lpData – argument to be passed to callback function (can be NULL)
pbCancel – operation canceled if it is set to TRUE
dwCopyFlags – specify, how file is to be copied

25. CopyProgressRoutine (1)

26. CopyProgressRoutine (2)
TotalFileSize – file size in bytes
TotalBytesTransferred – number of bytes already transferred
StreamSize – size of current stream in bytes
SteramBytesTransferred – number of bytes already transferred from current stream
dwStreamNumber – handle to current stream
dwCallbackReason – reason this function was called
hSourceFile – handle to the source file
hDestinationFile – handle to the destination file
lpData – data from CopyFileEx function

27. dwCallbackReason There are two reasons:
CALLBACK_CHUNK_FINISHED – part of data was copied
CALLBACK_STREAM_SWITCH – another stream created and is about to be copied

28. CopyProgressRoutine (3)
This function returns:
PROGRESS_CONTINUE – continue copying
PROGRESS_CANCEL – cancel copying and delete destination file
PROGRESS_STOP – stop copying (can be restarted later)
PROGRES_QUIET – continue copying without invoking callback function

29. MoveFile[Ex]

30. DeleteFile & RemoveDirectory

31. Other features Enumeration Locking Encoding Archiving Memory-mapping
etc.

32. CloseHandle Handles must be closed
When program is closing, OS automatically closes all associated handles
expensive operation
handle leak
For sockets – closesocket
For registry keys - RegCloseKey

33. Handle leaks When closing handle fails: Memory isn’t freed
Kernel keeps all information about handle
Sluggish system
Crash