For compatibility reasons with older releases, calling this function
is not strictly required, the resources will be automatically freed
when the cancellable is finalized. However, the cancellable will
block scarce file descriptors until it is finalized if this function
is not called. This can cause the application to run out of file
descriptors when many gio.Cancellables are used at the same time.
Releases a resources previously allocated by Cancellable.getFd or Cancellable.makePollfd.
For compatibility reasons with older releases, calling this function is not strictly required, the resources will be automatically freed when the cancellable is finalized. However, the cancellable will block scarce file descriptors until it is finalized if this function is not called. This can cause the application to run out of file descriptors when many gio.Cancellables are used at the same time.