@paramin VariableName A Null-terminated string that is the name of the vendor's
variable.
@paramin VendorGuid A unique identifier for the vendor.
@paramout Attributes If not NULL, a pointer to the memory location to return the
attributes bitmask for the variable.
@param[in, out] DataSize On input, the size in bytes of the return Data buffer.
On output the size of data returned in Data.
@paramout Data The buffer to return the contents of the variable.
@retval EFI_SUCCESS The function completed successfully.
@retval EFI_NOT_FOUND The variable was not found.
@retval EFI_BUFFER_TOO_SMALL The DataSize is too small for the result.
@retval EFI_INVALID_PARAMETER VariableName is NULL.
@retval EFI_INVALID_PARAMETER VendorGuid is NULL.
@retval EFI_INVALID_PARAMETER DataSize is NULL.
@retval EFI_INVALID_PARAMETER The DataSize is not too small and Data is NULL.
@retval EFI_DEVICE_ERROR The variable could not be retrieved due to a hardware error.
@retval EFI_SECURITY_VIOLATION The variable could not be retrieved due to an authentication failure.
Returns the value of a variable.
@paramin VariableName A Null-terminated string that is the name of the vendor's variable. @paramin VendorGuid A unique identifier for the vendor. @paramout Attributes If not NULL, a pointer to the memory location to return the attributes bitmask for the variable. @param[in, out] DataSize On input, the size in bytes of the return Data buffer. On output the size of data returned in Data. @paramout Data The buffer to return the contents of the variable.
@retval EFI_SUCCESS The function completed successfully. @retval EFI_NOT_FOUND The variable was not found. @retval EFI_BUFFER_TOO_SMALL The DataSize is too small for the result. @retval EFI_INVALID_PARAMETER VariableName is NULL. @retval EFI_INVALID_PARAMETER VendorGuid is NULL. @retval EFI_INVALID_PARAMETER DataSize is NULL. @retval EFI_INVALID_PARAMETER The DataSize is not too small and Data is NULL. @retval EFI_DEVICE_ERROR The variable could not be retrieved due to a hardware error. @retval EFI_SECURITY_VIOLATION The variable could not be retrieved due to an authentication failure.