mila6452, on 2012-October-22, 18:03, said:
If you understand the syntax of the md|| tag, than you can simply rotate/change the deal. If you have a look it would very easy. (The order is: South-West-North(-East); The first number defines the dealer: 1=South)
The sv|| tag will set vulnerability: n (NS) , e ( EW) , b(both), 0 ( none ) , as sv|n|,sv|e|,sv|b|,sv|0|.
That effectively rotates it, but only with respect to who is opener, and as you mention, you need to alter vulnerability, if it was only one way before. But the hand that is South in the original remains South after the "rotation".
In answer to the original question, you could write a little "program", e.g. in python, but the format of the .lin file will force you to fill in the missing hand! The BBO lin file always starts with South (or West), the opposite of pbn, and leaves the fourth hand unspecified after the last comma in that section. So your rotation program needs to "fill in the 4th hand", then rotate. I am not sure whether you then need to blank the new 4th hand. I suspect you can specify all 4, but I have not tried it.
I noticed this two weekends ago, when writing a converter from .lin to pbn for a DD program that I had.