From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on inbox.vuxu.org X-Spam-Level: X-Spam-Status: No, score=-1.1 required=5.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,MAILING_LIST_MULTI autolearn=ham autolearn_force=no version=3.4.4 Received: (qmail 8040 invoked from network); 10 Dec 2022 19:39:12 -0000 Received: from minnie.tuhs.org (50.116.15.146) by inbox.vuxu.org with ESMTPUTF8; 10 Dec 2022 19:39:12 -0000 Received: from minnie.tuhs.org (localhost [IPv6:::1]) by minnie.tuhs.org (Postfix) with ESMTP id C9004423B0; Sun, 11 Dec 2022 05:39:04 +1000 (AEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=tuhs.org; s=dkim; t=1670701144; h=from:from:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding:list-id:list-help: list-owner:list-unsubscribe:list-subscribe:list-post; bh=troxMZUxVhoReIwDN8BJqrhkBgf8WTmXBxTfzJ0eWEI=; b=hwrUIyyvhhfLPbWImK557B5NQcUO2zIq1diKln7xW9cIsrd20EiM23MGdf647UPkII4JpW Pfc5FKOyxwJ6ZRnhKXNN0mSp4cGC1COske88hI4iWLZqeislAfLhcqDFvO0oFFc8nOWEjX ogPCq3R9gRLS27rR2rMHdNJ8WsX19n0= Received: from mail-4318.protonmail.ch (mail-4318.protonmail.ch [185.70.43.18]) by minnie.tuhs.org (Postfix) with ESMTPS id 3553C423AF for ; Sun, 11 Dec 2022 05:38:51 +1000 (AEST) Date: Sat, 10 Dec 2022 19:38:45 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=protonmail.com; s=protonmail3; t=1670701128; x=1670960328; bh=troxMZUxVhoReIwDN8BJqrhkBgf8WTmXBxTfzJ0eWEI=; h=Date:To:From:Subject:Message-ID:Feedback-ID:From:To:Cc:Date: Subject:Reply-To:Feedback-ID:Message-ID:BIMI-Selector; b=pE/U1cYvFPURhxHqK18z6oD4ouKtjT1Jf9DFBDofPxEg3dLxxtIbWSz455EsALRy2 Z0A/rQsPpy7Fu95yIndrgyXPeg5dF1PX1w1ybkn87T2lAlOZLFGbWbntaYCZDbP6OF +JAOysGmfY2myxOAP8IIsy+mjmJyWMqKn9br/51y6434uYNz/uBM4gNmWzP7D+Upxv ++IGjjj3MWSeL88sdwg5vqh1R/JbcnKt0xYJGwcLm5N11K57nCcxwoKp+tLMWFy0uy nuJ86JMUnS1eenEfwWfuhJwh2o4HyEYI9wKv86mT9tj5fD+fIUVdzDziLlI92A3Wad bmJHG9uBbiGAw== To: The Eunuchs Hysterical Society Message-ID: <9QJtlCA0hfDuNuwOqorx1uC2eSGOiIBu0hgsVAaKclEWUw4Gi9PAjJoZgcOF7W6rRCw4XqM3wBZMavgF_HEH4GR2WuczKF5w_tZAjAXgzlE=@protonmail.com> Feedback-ID: 35591162:user:proton MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Message-ID-Hash: JXTIHJM3EFUX67BPCRT4TYTGSDBSFC3Z X-Message-ID-Hash: JXTIHJM3EFUX67BPCRT4TYTGSDBSFC3Z X-MailFrom: segaloco@protonmail.com X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation; header-match-tuhs.tuhs.org-0; nonmember-moderation; administrivia; implicit-dest; max-recipients; max-size; news-moderation; no-subject; digests; suspicious-header X-Mailman-Version: 3.3.6b1 Precedence: list Subject: [TUHS] Stdin Redirect in Cu History/Alternatives? List-Id: The Unix Heritage Society mailing list Archived-At: List-Archive: List-Help: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: From: segaloco via TUHS Reply-To: segaloco Good morning all. I've been doing some historical research on the UUCP cu = utility this morning and have come across a little discrepancy between the = various UNIX streams I was wondering if someone could illuminate. So cu as of V7 supported the ~$ escape, a means of calling a local procedur= e and emitting stdout over the TTY line to the remote machine, all fine and= good for packaging a character stream to emit. However, what I'm not find= ing in that age of documentation is any means of requesting std*in* from th= e TTY line as input to a local procedure (in essence running a text filter = or handshake-driven protocols over cu). The context in which I'm researchi= ng this is integrating cu into my bare-metal SBC programming using XMODEM s= o I can rest a little easier my process is based on tools I'll probably fin= d in most places. So old fashioned Mike Lesk-era cu only seems to do stdout redirect, but no = stdin. I did some further digging and it looks like different UUCP impleme= ntations cracked this nut with different escapes, with BSD eventually going= with ~C and Taylor UUCP opting for ~+. Checking the current illumos manua= l pages (for a SVR4-ish example) doesn't turn up any command for this. Thi= s is indicative of there never being an agreed-upon mechanism for doing thi= s, although I could see this being a very useful mechanism. What I'm curious about is if the lack of a bi-directional redirect in early= cu is reflective of a lack of need for that sort of functionality at the t= ime or that matters such as that were handled through a different mechanism= . One thought I did have is that there wasn't file locking at the time (ri= ght?) and so theoretically nothing would prevent one from using a cu sessio= n on one terminal to send interactive commands and then a second using fd r= edirects in the shell to run filters/protocols separately of the interactiv= e stream. - Matt G.