is RECVFROM atomic?

[Ken Greer]

Are packets received by recvfrom atomic?  That is, if I request 256
bytes will I ever get less?  If I set non-blocking (NDELAY) mode,
I can recieve 0 bytes, but can I receive a partial packet?
I've searched all the documentation I have with no help.

Ken Greer  Elan Computer Group, Inc. 888 Villa St. 3rd Floor Mt View CA 94041
Phone:     415-964-2200
Internet:  kg at elan.com
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