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Function USBMTPGetFile

USBMTPGetFile retrieves a file from a USB MTP device:

typedef void (RTTAPI * USBMTPDataCallback) (void * P, void * Data, UINT Len); 

int USBMTPGetFile(int                 Dev, 
                  USBMTPHandle        Handle, 
                  USBMTPFileInfo    * Info, 
                  void              * P, 
                  USBMTPDataCallback  Callback);

Parameters

Dev

Index of the MTP device. This value should be in range 0 .. RTUSBMTPConfig.MaxDevices - 1.

Handle

Handle of the file to retrieve. This handle could have been retrieved through functions USBMTPFindFirstFile/USBMTPFindNextFile.

Info

Pointer to a structure to receive information about the specified file. This parameter is optional and may be NULL. For more information about this parameter, please see function USBMTPGetFileInfo.

P

An arbitrary value that will be passed on to parameter Callback.

Callback

A pointer to a function to be called by USBMTPGetFile to pass the file's data on to the application.

return value

If successful, a value >= RTU_SUCCESS is returned, otherwise, a negative error code.

This function reads data from the MTP device into its internal buffer and then calls the function specified in parameter Callback with the parameter P passed to USBMTPGetFile, a pointer to its internal buffer, and the number of bytes in the buffer. The callback should typically write the data to a file or consume the data in some other way. The callback is called repeatedly until all of the file's data has been transferred.

Function Get of demo program MTPDemo shows how this function is used.

Function USBMTPSetFileProperty

Function USBMTPPutFile