X-Recipient: archive-cygwin AT delorie DOT com
X-Original-To: cygwin AT cygwin DOT com
Delivered-To: cygwin AT cygwin DOT com
DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org C5A2C3858D28
Authentication-Results: sourceware.org; dmarc=none (p=none dis=none)
 header.from=SystematicSw.ab.ca
Authentication-Results: sourceware.org;
 spf=none smtp.mailfrom=systematicsw.ab.ca
X-Authority-Analysis: v=2.4 cv=I4EG+Psg c=1 sm=1 tr=0 ts=615b1fb4
 a=T+ovY1NZ+FAi/xYICV7Bgg==:117 a=T+ovY1NZ+FAi/xYICV7Bgg==:17
 a=AptXmjEDr1eunWyc:21 a=IkcTkHD0fZMA:10 a=w_pzkKWiAAAA:8
 a=JMgxg57iEJyXohXag2sA:9 a=QEXdDO2ut3YA:10 a=4Nq_U35Bjeu8yGpTXatc:22
 a=sRI3_1zDfAgwuvI8zelB:22
To: cygwin AT cygwin DOT com
References: <0f3a01d7b873$3fa7f280$bef7d780$@pdinc.us>
 <20211004045817 DOT a9973070199874e420909fcd AT nifty DOT ne DOT jp>
From: Brian Inglis <Brian DOT Inglis AT SystematicSw DOT ab DOT ca>
Organization: Systematic Software
Subject: Re: is there a limit on how many mintty terminals can be open at once?
Message-ID: <581b2204-da47-b104-4735-20b35af13f9b@SystematicSw.ab.ca>
Date: Mon, 4 Oct 2021 09:37:23 -0600
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101
 Thunderbird/78.14.0
MIME-Version: 1.0
In-Reply-To: <20211004045817.a9973070199874e420909fcd@nifty.ne.jp>
Content-Language: en-CA
X-CMAE-Envelope: MS4xfOJzl7qTuAR69JHyDFg1PbC5tj0FUteY/sn2S7kG0ssmJADMTpB790K7s//PPjR2MlDxhClMk1DurHFRHsUL40Ue2dMGHmurrVR04mkj8DBV49UB92Yt
 UArNTVYE9pUzRMlAA97mhs7whPiKTY8E6VbAxMrdRocgFEQrKiyW+ul03gT3/RO7uYdzYA8+5FA9m1atTUwzuarGbD82qKgDkwc=
X-Spam-Status: No, score=-1160.8 required=5.0 tests=BAYES_00, KAM_DMARC_STATUS,
 KAM_LAZY_DOMAIN_SECURITY, NICE_REPLY_A, RCVD_IN_BARRACUDACENTRAL,
 RCVD_IN_DNSWL_NONE, RCVD_IN_MSPIKE_H4, RCVD_IN_MSPIKE_WL, SPF_HELO_NONE,
 SPF_NONE, TXREP autolearn=no autolearn_force=no version=3.4.4
X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on
 server2.sourceware.org
X-BeenThere: cygwin AT cygwin DOT com
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: General Cygwin discussions and problem reports <cygwin.cygwin.com>
List-Unsubscribe: <https://cygwin.com/mailman/options/cygwin>,
 <mailto:cygwin-request AT cygwin DOT com?subject=unsubscribe>
List-Archive: <https://cygwin.com/pipermail/cygwin/>
List-Post: <mailto:cygwin AT cygwin DOT com>
List-Help: <mailto:cygwin-request AT cygwin DOT com?subject=help>
List-Subscribe: <https://cygwin.com/mailman/listinfo/cygwin>,
 <mailto:cygwin-request AT cygwin DOT com?subject=subscribe>
Reply-To: cygwin AT cygwin DOT com
Content-Transfer-Encoding: 7bit
Content-Type: text/plain; charset="us-ascii"; Format="flowed"
Errors-To: cygwin-bounces+archive-cygwin=delorie DOT com AT cygwin DOT com
Sender: "Cygwin" <cygwin-bounces+archive-cygwin=delorie DOT com AT cygwin DOT com>

On 2021-10-03 13:58, Takashi Yano via Cygwin wrote:
> On Sun, 3 Oct 2021 12:25:15 -0400
> "Jason Pyeron" wrote:
>> I got the "Error: Could not fork child process: There are no
>> available terminals (-1)" error.
>> Closing N minty terminals allowed me to open exactly N more.
>> My google fu is poor, since I cannot seem to find relevant pages.
>> What is the limit?

> In current cygwin, maximum number of pty is 128.
> It is hard coded and not configurable by user.
> https://cygwin.com/git/?p=newlib-cygwin.git;a=blob;f=winsup/cygwin/tty.h#l15

Why would you want and how could you use 128 local terminal windows on 
one system, where could you put them, and be able to read them, unless 
you are building some kind of control centre, and then wouldn't GUI 
processes forked under a windows system be more useful?

There is no longer much of a limit on Cygwin 64 processes, so you could 
fork thousands of bash or any other exe processes under each terminal.

I know sysadmins who used dozens of terminal windows, but only a few 
active at a time, and they were ssh sessions to remote systems 
displaying X terminals on their desktop X server.

I've never needed more than a few terminal windows on a few systems at a 
time, but I come from the school of closing windows as soon as I don't 
need them, to reduce load, and avoid typing any command in the wrong 
window! One "Oh sh***!" is all you need ;^>

-- 
Take care. Thanks, Brian Inglis, Calgary, Alberta, Canada

This email may be disturbing to some readers as it contains
too much technical detail. Reader discretion is advised.
[Data in binary units and prefixes, physical quantities in SI.]

[The most I've deployed was a few stations at diverse locations with 12 
windows on six screens remoting into servers running 12 front ends for a 
trading platform to reduce latency of server process transaction 
execution to low ms.]

-- 
Problem reports:      https://cygwin.com/problems.html
FAQ:                  https://cygwin.com/faq/
Documentation:        https://cygwin.com/docs.html
Unsubscribe info:     https://cygwin.com/ml/#unsubscribe-simple