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3.8.5 Blocking computation

IMAGE descriptors have a flag called kill which can be used to block computation. If im->kill is set to a non-zero value, then any VIPS pipelines which use im as an intermediate will fail with an error message. This is useful for user-interface writers -- suppose your interface is forced to close an image which many other images are using as a source of data. You can just set the kill flag in all of the deleted image's immediate children and prevent any dangling pointers from being followed.



John Cupitt 2004-11-02