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dbOpenCellViewByType question

nosaj

 Hi all,

 I'm writing a procedure that creates a library and layout views and it seems to work ok except when I try to open the Top cell that's created from my procedure, I'll get a warning :

*WARNING* (LE-104268): LibX/Top/layout has already been opened in edit mode.

When I try to close the cellview, it'll ask me if I want to save the changes, even though no changes were made. if I say NO, then reopen the cell, everything's gone.  If I say YES, what I've created from the SKILL will get saved. This behavior only happens on the Top cell where I create last. But I'm creating it the same way other cells are created. The warning is still there even though I've saved the top cell already.  it's as if I have it opened else where.  Also, when opening the subcell created, I'll get the warning but won't ask me to save changes.

I make sure to dbSave and dbClose all the cellview I have opened in "w" mode and "r" mode.  (see below)

Any idea what causes this?  I welcome any suggestion.

;====================================================

topId=dbOpenCellViewByType(lib top "layout" "maskLayout" "w")
...

cellId=dbOpenCellViewByType(lib cell "layout" "maskLayout" "r")
inst=dbCreateInst(topId cellId ........)
dbClose(cellId)

.....

dbSave(topId)
dbClose(topId)

 ;====================================================

  • Hi Nosaj,

    Perhaps the problem is that "cell" can be equal to "top" at some point?  It is not possible to open the cellview in read mode when it is already opened in write/append mode in virtual memory, so you will get two references to the cellview and both "topId" and "cellId" will point to the same cellview database object - the cellview is opened once for efficiency and "cellId" is a second pointer to the same object in virtual memory.

    If this is not the case then I am not sure what is happening, however, if you do have multiple "pointers" to the cellview database ID open, calling dbClose() multiple times until it returns 'nil' should close each one out until the cellview is purged from VM.

    Hope this helps.

    Lawrence.

  • Another possibility is that the variable top is being used elsewhere in you code and has not been properly declared as a local variable and is being overwritten. So top at the beginning ends up being different from top at the end (where the save occurs).

    If you have the SKILL development license, you could use:

    tracev(topId)

    To see when the variable is being set - and track the different values. Maybe also:

    trace(dbSave dbOpenCellViewByType)

    Regards,

    Andrew

  • I think the multiple cell pointers is probably what is happening. You can use dbPurge instead of dbClose to make sure all pointers to the cell are removed. You can also force it back to read mode with dbReopen(cv "r").

    Do you need to open the cell in "w" mode? Are you creating it from scratch? Using "w" instead of "a" would explain why the cell ends up empty after a save.

     Derek

  • turns out there were multiple "pointers" which was causing the issue.

    thank you all for your inputs! 

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