Open Event

Fires when the OS wants to open a file.

Syntax

class FUSEOpenEventParams {
public:
  const QString &Path();
  int Flags();
  bool DirectIO();
  void SetDirectIO(bool bDirectIO);
  bool KeepCache();
  void SetKeepCache(bool bKeepCache);
  bool NonSeekable();
  void SetNonSeekable(bool bNonSeekable);
  int FileContext();
  void SetFileContext(int iFileContext);
  int Result();
  void SetResult(int iResult);
  int EventRetVal();
  void SetEventRetVal(int iRetVal);
};
// To handle, connect one or more slots to this signal. void Open(FUSEOpenEventParams *e);
// Or, subclass FUSE and override this emitter function. virtual int FireOpen(FUSEOpenEventParams *e) {...}

Remarks

This event fires when the OS wants to open the existing file specified by Path using the open options reflected in Flags. The set of possible flags and options corresponds to the Flags parameter of Linux open(2) call.

The application may use the FileContext parameter to store a file handle or other information, related to the open file. Windows: the stored information will be shared between all concurrent file open operations performed on this file.

Linux: DirectIO parameter may be set by the application to tell the kernel that buffering or caching should be avoided. KeepCache parameter may be set by the application to tell the kernel that existing file caches (if any) should not be invalidated. NonSeekable parameter may be set by the application to tell the kernel that the file is not seekable.

The ResultCode parameter will always be 0 when the event is fired. If the event cannot be handled in a "successful" manner for some reason (e.g., a resource isn't available, security checks failed, etc.), set it to a negative error code value (e.g. -ENOENT to indicate that the file does not exist) to report an appropriate error. Please refer to the Error Reporting and Handling topic for more information.

Copyright (c) 2022 Callback Technologies, Inc. - All rights reserved.
CBFS FUSE 2020 Qt Edition - Version 20.0 [Build 8348]