(ITS#4945) slapd drops connections during search results

[mhardin@symas.com]

Full_Name: Matthew Hardin
Version: 2.3.35
OS: Windows 2003
URL: ftp://ftp.openldap.org/incoming/
Submission from: (NULL) (170.215.67.85)


If Winsock returns EWOULDBLOCK while sending search results to a client, slapd
will stop sending results and close the connection.

The problem is in openldap/servers/slapd/result.c at line 173, where it
incorrectly checks errno. It should be checking sock_errno().

I note that HEAD already does this.