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This function creates, opens, or truncates a file, pipe, communications resource, disk device, or console. It returns a handle that can be used to access the object. It can also open and return a handle to a directory.
CeCreateFileis a remote application interface (RAPI), which enables an application running on a desktop computer to make function calls on a Windows CE–based device.
HANDLE CeCreateFile( LPCWSTR lpFileName , DWORD dwDesiredAccess , DWORD dwShareMode , LPSECURITY_ATTRIBUTES lpSecurityAttributes , DWORD dwCreationDisposition , DWORD dwFlagsAndAttributes , HANDLE hTemplateFile );
Parameters
If lpFileNameis a path, there is a default string size limit of MAX_PATH characters. This limit is related to how the CeCreateFilefunction parses paths.
You can use paths longer than MAX_PATH characters by prepending "\\?\" to the path. The "\\?\" tells the function to turn off path parsing. This lets you use paths that are nearly 32,000 Unicode characters long. However, each component in the path cannot be more than MAX_PATH characters long. You must use fully-qualified paths with this technique. This also works with Universal Naming Convention (UNC) names. The "\\?\" is ignored as part of the path. For example, "\\?\C:\myworld\private" is seen as "C:\myworld\private" and "\\?\UNC\tom_1\hotstuff\coolapps" is seen as "\\tom_1\hotstuff\coolapps."
Value | Description |
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0 | Specifies device query access to the object. An application can query device attributes without accessing the device. |
GENERIC_READ | Specifies read access to the object. Data can be read from the file and the file pointer can be moved. Combine with GENERIC_WRITE for read-write access. |
GENERIC_WRITE | Specifies write access to the object. Data can be written to the file and the file pointer can be moved. Combine with GENERIC_READ for read-write access. |
To share the object, use a combination of one or more of the following values:
Value | Description |
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FILE_SHARE_READ | Subsequent open operations on the object will succeed only if read access is requested. |
FILE_SHARE_WRITE | Subsequent open operations on the object will succeed only if write access is requested. |
Value | Description |
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CREATE_NEW | Creates a new file. The function fails if the specified file already exists. |
CREATE_ALWAYS | Creates a new file. If the file exists, the function overwrites the file and clears the existing attributes. |
OPEN_EXISTING | Opens the file. The function fails if the file does not exist. |
See the Remarks section for a discussion of why you should use the OPEN_EXISTING flag if you are using the CeCreateFilefunction for devices, including the console. | |
OPEN_ALWAYS | Opens the file, if it exists. If the file does not exist, the function creates the file as if dwCreationDispositionwere CREATE_NEW. |
TRUNCATE_EXISTING | Opens the file. Once opened, the file is truncated so that its size is zero bytes. The calling process must open the file with at least GENERIC_WRITE access. The function fails if the file does not exist. |
Any combination of the following attributes is acceptable for the dwFlagsAndAttributesparameter, except all other file attributes override FILE_ATTRIBUTE_NORMAL.
Value | Description |
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FILE_ATTRIBUTE_ARCHIVE | The file should be archived. Applications use this attribute to mark files for backup or removal. |
FILE_ATTRIBUTE_HIDDEN | The file is hidden. It is not to be included in an ordinary directory listing. |
FILE_ATTRIBUTE_NORMAL | The file has no other attributes set. This attribute is valid only if used alone. |
FILE_ATTRIBUTE_READONLY | The file is read only. Applications can read the file but cannot write to it or delete it. |
FILE_ATTRIBUTE_SYSTEM | The file is part of or is used exclusively by the operating system. |
FILE_ATTRIBUTE_TEMPORARY | This attribute flag is not supported; however, if you have an installed file system that supports FILE_ATTRIBUTE_TEMPORARY, you can set or receive this flag. For example, the network redirector shows this flag if you are talking to a computer running Windows NT. Also, if you have a flash card inserted, the attributes of \StorageCard include the temporary bit. |
Any combination of the following flags is acceptable for the dwFlagsAndAttributesparameter.
Value | Description |
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FILE_FLAG_WRITE_THROUGH | Instructs the system to write through any intermediate cache and go directly to disk. The system can still cache write operations, but cannot lazily flush them. |
FILE_FLAG_OVERLAPPED | This flag is not supported; however, multiple reads/writes pending on a device at a time are allowed. |
FILE_FLAG_RANDOM_ACCESS | Indicates that the file is accessed randomly. The system can use this as a hint to optimize file caching. |
Return Values
An open handle to the specified file indicates success. If the specified file exists before the function call and dwCreationDispositionis CREATE_ALWAYS or OPEN_ALWAYS, a call to GetLastErrorreturns ERROR_ALREADY_EXISTS, even though the function has succeeded. If the file does not exist before the call, GetLastErrorreturns zero. INVALID_HANDLE_VALUE indicates failure. To determine if a function failed because of RAPI errors, call CeRapiGetError.
Remarks
When writing applications for Windows CE version 1.0 and 1.01, use the PegCreateFilefunction.
Requirements
Runs On | Versions | Defined in | Include | Link to |
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Windows CE OS | 2.0 and later | Rapi.h |
See Also
CeRapiGetError, CreateFile, GetLastError