[lwip-users] Re: [lwip] pbuf payload length

[Jani Monoses]

Just to make sure I understand what you want to accomplish 
-you have a linear data buf of size len  in memory.
-you want it copied to a possibly chained pbuf which you know(?) has tot_len 
>=len
correct?
If it's a one time copy it's easy do a pbuf_realloc(p,len) and the copy 
the data over by walking the chain.

However if you want to call copy_data2pbuf() repeatedly on the same pbuf then 
as you say you should keep an external var.

In ip_frag.c in CVS there's a copy_from_buf() which does the opposite:copies 
from
a chained pbuf to linear memory keeping track of the offset and current pbuf in 
chain.
If it's similar to what you need then it's easy to modify.

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