Memory only scratch view

Hi Ted,

Yes, but there are no public APIs for it because not everything is guaranteed to work with them. They are currently reserved for specific internal Cadence applications where we know that the usage is limited to features that will work (e.g. transient rulers in the layout editor).

Regards,

Andrew.

Thanks, Andrew

I was trying not to have to create a new temporary scratch library as the design library may not be writable.

I want to represent nested shapes found with dbGetTrueOverlaps as top level shapes but not put them in the current cellView where they would have to be deleted after they have served their purpose.

There seems to be a way to create an extension to a library in the cds.lib which uses the assign keyword:

ASSIGN <libName> TMP </tempDirectory>

The documentation says that this can be used by applications for derived data such as derived cellViews. How does one create a cellView which is guaranteed to be be in this temp directory which would be writable?

Thanks

Ted

Hi Ted,

Unfortunately, that's not really what ASSIGN TMP is for. It's for adding auxiliary data (such as AMS cell-based netlists, NCSIM compilation results etc) - not for whole new cellViews. So I believe that if you create the cellView, it would still create it in the main library (or attempt to, at least).

Regards,

Andrew.

Thanks Andrew

The documentation was talking about views and I was just trying to keep from having to create a new library.

For those who are interested in using scratch cell architecture, here is what I am implementing:

I will set it up when the "UseScratchLib.ils" package is loaded by a libInit so it will create a new scratch library in the user's temp directory.

The pointers to the library and any open cellViews will be kept as private variables in a closure. The code must check for valid library and cellView when creating/accessing data.

Data will be copied into the scratch cellView and out back into the live cellView as necessary.

The scratch library will be deleted when Virtuoso is exited. It will be removed from the cds.lib file as well.

This should work even in non graphics mode or when translating to GDS2.

Ted