Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!ucbvax!VAX.FTP.COM!jbvb
From: jbvb@VAX.FTP.COM (James Van Bokkelen)
Newsgroups: comp.protocols.tcp-ip.ibmpc
Subject: Re: advice on software
Message-ID: <8908181715.AA22284@vax.ftp.com>
Date: 18 Aug 89 17:15:03 GMT
References: <8908171600.AA19853@mcvax.cwi.nl>
Sender: daemon@ucbvax.BERKELEY.EDU
Organization: The Internet
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Some more information on TCP connections vs. descriptors in PC/TCP:

DOS 3.x has a limit of 20 file descriptors per process.  Our "local"
network descriptors are mapped to DOS file descriptors (the socket
library uses them to talk to the kernel), so you can't have more than
20 of them per-process (you could probably get above 16 TCP
connections if you could close some of the stdio handles which occupy
descriptors 0-4).

The 2.0 kernel also supports "global" network descriptors, which aren't
mapped to DOS file handles, but for various reasons the socket library
can't use them.  If you code to our native-mode interface, you can
open 32 simultaneous TCP connections just fine (my test program does).

James B. VanBokkelen		26 Princess St., Wakefield, MA  01880
FTP Software Inc.		voice: (617) 246-0900  fax: (617) 246-0901