File Management

What is File? File I/O device: File stream Directory Physical disk Volume Console buffer Tape drive Communications resource Mailslot Pipe

HANDLE WINAPI CreateFile( _In_     LPCTSTR     lpFileName, _In_     DWORD       dwDesiredAccess, _In_     DWORD       dwShareMode, _In_opt_ LPSECURITY_ATTRIBUTES lpSecurityAttributes, _In_     DWORD       dwCreationDisposition, _In_     DWORD       dwFlagsAndAttributes, _In_opt_ HANDLE   hTemplateFile);

lpFileName The name of the file or device to be created or opened. Name can have either forward slashes (/) or backslashes (\) used.

dwDesiredAccess Requested access to the file or device: GENERIC_READ GENERIC_WRITE GENERIC_EXECUTE GENERIC_ALL Etc. If zero, querying some metadata available

dwShareMode Prevent sharing FILE_SHARE_DELETE Subsequent delete access Prevent sharing FILE_SHARE_DELETE Subsequent delete access FILE_SHARE_READ Subsequent read access FILE_SHARE_WRITE Subsequent write access

lpSecurityAttributes A pointer to a SECURITY_ATTRIBUTES Can be NULL (default security descriptor will be used) Child process can’t inherit file handle

dwCreationDisposition What action should be taken: CREATE_ALWAYS Allways creates file CREATE_NEW Creates file if not existing OPEN_ALWAYS Allways opens file OPEN_EXISTING Opens file if existing TRUNCATE_EXISTING Opens and clears file

dwFlagsAndAttributes FILE_ATTRIBUTE_ARCHIVE FILE_ATTRIBUTE_ENCRYPTED FILE_ATTRIBUTE_HIDDEN FILE_ATTRIBUTE_NORMAL 20 more…

hTemplateFile Handle to a template file - supplies file attributes and extended attributes

Is there something simple? HANDLE WINAPI CreateFile2( _In_     LPCWSTR lpFileName, _In_     DWORD dwDesiredAccess, _In_     DWORD dwShareMode, _In_     DWORD dwCreationDisposition, _In_opt_ LPCREATEFILE2_EXTENDED_PARAMETERS pCreateExParams);

Copy, transfer and renaming CopyFile CopyFile2 CopyFileEx

CopyFile lpExistingFileName – pointer to string lpNewFileName – pointer to string bFailIfExists – if TRUE, existing file will be not overwritten

CopyFileEx (1)

CopyFileEx (2) lpProgressRoutine – CALLBACK function, called after portion of file is copied lpData – argument to be passed to the CALLBACK function (can be NULL) pbCancel – if it becames TRUE during copy operation, operation is canceled dwCopyFlags – specify how the file is to be copied

dwCopyFlags COPY_FILE_ALLOW_DECRYPTED_DESTINATION COPY_FILE_FAIL_IF_EXISTS COPY_FILE_OPEN_SOURCE_FOR_WRITE COPY_FILE_RESTARTABLE

CopyProgressRoutine (1)

CopyProgressRoutine (2) TotalFileSize – file size in bytes TotalBytesTransferred – total transfered bytes StreamSize – current stream size in bytes StreamBytesTransferred – transfered bytes in stream dwStreamNumber – handle to current stream dwCallbackReason – reason why function was called hSourceFile – handle to source file hDestinationFile – handle to destination file lpData – argument from CopyFileEx function

dwCallbackReason CALLBACK_CHUNK_FINISHED CALLBACK_STREAM_SWITCH

CopyProgressRoutine (3) PROGRESS_CONTINUE PROGRESS_CANCEL PROGRESS_STOP PROGRESS_QUIET

MoveFile[Ex]

dwFlags MOVEFILE_COPY_ALLOWED MOVEFILE_CREATE_HARDLINK reserved MOVEFILE_DELAY_UNTIL_REBOOT MOVEFILE_FAIL_IF_NOT_TRACKABLE MOVEFILE_REPLACE_EXISTING MOVEFILE_WRITE_THROUGH

DeleteFile & RemoveDirectory

ReadFile BOOL WINAPI ReadFile( _In_ HANDLE hFile, _Out_ LPVOID lpBuffer, _In_ DWORD nNumberOfBytesToRead, _Out_opt_ LPDWORD lpNumberOfBytesRead, _Inout_opt_ LPOVERLAPPED lpOverlapped);

ReadFileEx BOOL WINAPI ReadFileEx( _In_ HANDLE hFile, _Out_opt_ LPVOID lpBuffer, _In_ DWORD nNumberOfBytesToRead, _Inout_ LPOVERLAPPED lpOverlapped, _In_ LPOVERLAPPED_COMPLETION_ROUTINE lpCompletionRoutine);

OVERLAPPED Structure to contain information for asynchronous (or overlapped) I/O typedef struct _OVERLAPPED { ULONG_PTR Internal; ULONG_PTR InternalHigh; union { struct { DWORD Offset; DWORD OffsetHigh; }; PVOID  Pointer; HANDLE    hEvent; } OVERLAPPED, *LPOVERLAPPED;

WriteFile BOOL WINAPI WriteFile( _In_ HANDLE hFile, _In_ LPCVOID lpBuffer, _In_ DWORD nNumberOfBytesToWrite, _Out_opt_ LPDWORD lpNumberOfBytesWritten, _Inout_opt_ LPOVERLAPPED lpOverlapped);

WriteFileEx BOOL WINAPI WriteFileEx( _In_ HANDLE hFile, _In_opt_ LPCVOID lpBuffer, _In_ DWORD nNumberOfBytesToWrite, _Inout_ LPOVERLAPPED lpOverlapped, _In_ LPOVERLAPPED_COMPLETION_ROUTINE lpCompletionRoutine );

OpenFile Creates, opens, reopens, or deletes a file Obsolete (use CreateFile) HFILE WINAPI OpenFile( _In_ LPCSTR lpFileName, _Out_ LPOFSTRUCT lpReOpenBuff, _In_ UINT uStyle);

Don’t forget to use CloseHandle to release resources. If not – some problems may occur.

Other “things” There are a lot of functions to manage files. Feel free to use MSDN library.