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From: mlevin@jade.tufts.edu
Newsgroups: comp.unix.programmer,comp.unix.questions
Subject: why would a socket read() set errno to EWOULDBLOCK but still read?
Message-ID: <1991Jun27.220701.21108@athena.mit.edu>
Date: 27 Jun 91 22:07:01 GMT
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Organization: Me, Myself, and I, inc.
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   I am doing a read() on a connected TCP socket (BSD 4.3) marked as
non-blocking. For some reason, the read returns the proper number of
characters read (or sometimes 0), but sets errno to EWOULDBLOCK. Why
is this? My program never did this before; I was under the impression
that if no data was available, it should return -1. Is this a possible
event, or am I trashing memory somewhere? Please reply to
mlevin@jade.tufts.edu. 

Mike Levin