Resetting line number in tcsh (history -L)

[Ilya Zakharevich]

I want to share the user input history of a shell time to time. With
tcsh,

alias synchistory 'history -S; history -L'

works fine as far as the history file is concerned (I have necessary
counts, merging etc enabled). However, it increments line numbers in
the in-memory shell history by 3200 each time it is called (this is
the count of lines to keep). This is too confusing.

One solution to this increment problem would be to reset the line
number to 0 (or some other suitable number) between `history -S' and
`history -L'. Is there a way to do this?

Thanks,
Ilya