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=-3.4 required=5.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FROM,HTML_MESSAGE,MAILING_LIST_MULTI, RCVD_IN_DNSWL_MED autolearn=ham autolearn_force=no version=3.4.4 Received: (qmail 16558 invoked from network); 8 Jan 2023 04:29:54 -0000 Received: from zero.zsh.org (2a02:898:31:0:48:4558:7a:7368) by inbox.vuxu.org with ESMTPUTF8; 8 Jan 2023 04:29:54 -0000 ARC-Seal: i=1; cv=none; a=rsa-sha256; d=zsh.org; s=rsa-20210803; t=1673152194; b=EBTppkb7Y3Wc7nKzdX/fTc4X6LnTYam7N+YPQ5WSmJG9qccwU8PqzMfIhxDsZg4ykWtY2JngQY 0Ro0MEotIbikRm+AK4zW3JOd9ivivemknAUkhXehpCm5DPj0C+qc2WfBt6Nx90ZmqO65DDAqUH 79N8uu+/DxQs87Xxb14VJJlNq/Wq9z80lzlN+lHf/cQlIU+9dvdCEARk3l0FW4Sa9ng1H9NDPo 7l6Tuy03XTORsFMLwEXGHZIax8OjgPIHMx5c+++AL5Vr3v2FikOHC1ghQt7p34bL7NXEAnyn9w UNaSyb6TbqnP+Q78DiGwFncI1M1y8gYPObWPhXMwkmppcA==; ARC-Authentication-Results: i=1; zsh.org; iprev=pass (mail-pl1-f176.google.com) smtp.remote-ip=209.85.214.176; dkim=pass header.d=gmail.com header.s=20210112 header.a=rsa-sha256; dmarc=pass header.from=gmail.com; arc=none ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed; d=zsh.org; s=rsa-20210803; t=1673152194; bh=AFhhmlLuCIAOZCnLXMMmcgsP/FI4oVbdMU5ZtrdtIC0=; h=List-Archive:List-Owner:List-Post:List-Unsubscribe:List-Subscribe:List-Help: List-Id:Sender:Content-Type:Cc:To:Subject:Message-ID:Date:From:Reply-To: In-Reply-To:References:MIME-Version:DKIM-Signature:DKIM-Signature; b=RhxtVRpjHG31U4W3X8P6cPV2d8dyLoRTF+33EWq3qvrrpns60rKhznHFk+Jq2fxaUo1f1MLZCf 0quSezSXgkMQMPh2S3CPtyqMsa7BBEYBMWVdRMwowdCfAS/yoScjaN9WLSiIZFFxJFAknJkRfN TBAULAdNwPGFGN/cfD2fQoE/pTrOMhRfE2cQnZbiYhJ9YzF2k9pqXCzjRSfyp3B0ly+AKUCcom KbUEyDemNu19TJzqx2MmL4TZr9H1LUxxLpbnId/Ny4OO94B9pF95LruzlYviyGrYbxfHW9u5e6 Z99XkYROw3D0+h/hJHVc5vdHMh7/dNL6J/55X33XKGJw8w==; DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=zsh.org; s=rsa-20210803; h=List-Archive:List-Owner:List-Post:List-Unsubscribe: List-Subscribe:List-Help:List-Id:Sender:Content-Type:Cc:To:Subject:Message-ID :Date:From:Reply-To:In-Reply-To:References:MIME-Version: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID; bh=acBXStdGDUOl5p8Ql7DIX//OBpWkTcXDfhOtt0hDSpI=; b=QIE8fZe8I/9xAASVQHl0q5i0ep y8cZwzHcpWWZHs4J26NGzdTgCuenxuqfuVUrKNz7AMuweXF5/rU/xRqIQJnJAF8RlQ1JQRsYVrk7R xOZI9gY63C6XOvXaftRhyPhtVg1PYg5ZoGSo2GhLPFgusr93pBSsnIsF8Z8h4hgDDe9CzhEDRdEn8 ZBm2Z+Q1uDXdfS9wcn4Rk67HHSOl1wG6KC37nwMfToP0fxxQvt+o6uajRzf2QEQMbJ7J2KzHGHpLS oi4sVtkUprf54Nww8yMW/zyFvmNbTtdrFXWwHvOmTEsoa3oXBfBVEAuQWCf1h5xIpRDMd2wNPkyyg Pa0Rm2jw==; Received: by zero.zsh.org with local id 1pENJg-0009Tk-Ar; Sun, 08 Jan 2023 04:29:52 +0000 Authentication-Results: zsh.org; iprev=pass (mail-pl1-f176.google.com) smtp.remote-ip=209.85.214.176; dkim=pass header.d=gmail.com header.s=20210112 header.a=rsa-sha256; dmarc=pass header.from=gmail.com; arc=none Received: from mail-pl1-f176.google.com ([209.85.214.176]:41494) by zero.zsh.org with esmtps (TLS1.3:TLS_AES_128_GCM_SHA256:128) id 1pENJ2-0008lK-7i; Sun, 08 Jan 2023 04:29:12 +0000 Received: by mail-pl1-f176.google.com with SMTP id jl4so6014104plb.8 for ; Sat, 07 Jan 2023 20:29:11 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=cc:to:subject:message-id:date:from:reply-to:in-reply-to:references :mime-version:from:to:cc:subject:date:message-id:reply-to; bh=acBXStdGDUOl5p8Ql7DIX//OBpWkTcXDfhOtt0hDSpI=; b=pTqkwZeJyaL4McTsDXe/ppRWYG0BaZoa/qZmaxrD+kf6YUQpWmVz8RXpr/C1bSNNeT jBcBQjnWjWCDSmnvj/KS7jr0Kti5yqy9H2XAMTlHWR5vElUXzt3wsTI711zAFDFwt3py PeAEhA31fs6piV2db4joKV/v0GgQ7Fkrl95u4KRi5/1LcPABqtKTOMkhsSwErxLyBYCZ nZc3Alm2g1fj4GM0NyqytQ7iBVa+L2TLrj4jAhj90gD6QfuTNLxtXjanB3i/1B8/FA60 9c9NULtnPWSR3uY59eepUkIiFFWFrsoJ+4YqtM22CbklQAT9odilvXdimyOmVYHlRp1K /y9Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:subject:message-id:date:from:reply-to:in-reply-to:references :mime-version:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=acBXStdGDUOl5p8Ql7DIX//OBpWkTcXDfhOtt0hDSpI=; b=oCcjEZTp13X1kmfU947K5Ofy3BWjts1Rr5lHBz8TMHDGhJdDBr2KMk3W++ly7Vqtvs dXNlPnU8yeuw7/G4e/HcKQMheF4k2xsP83bErHwM/NY+8SvoyhTqsfyf/G/8Yi/XU93z 1lOps89KITQg2C8xE0aW5aOzXTaSb9RLbxmxrG8A9Bjeu10eaYmD1n7Vtc9s07Fyqn0Q KPiOujNsRPd+Cpkzy1RQrmta5yLoZv+MS2RzvdJvvwLp8yHmNnjfLKY9TQ3WTXtlIstM 1gPJVXAUc0k8S45eTM01KaZjOoKiYSrQdXdMR+CzdasYE3sojLRmv/t70D6kIYjLxR99 anlw== X-Gm-Message-State: AFqh2kro6GFTcQZrNJBF3KXcB3oO9dVlLqu/du0LLTWqdqq8/qsLxKfK JWTThr0qEeOzDhLXRGTb8uaZegnw0N/SYNF8SrY= X-Google-Smtp-Source: AMrXdXt6ylKURChaR9+JQrb2Q7KYGYgnO4U478mmzgZCUaokOLsSOYX1PCI0B/NS94jhmi9slBeFVJpnwYM9Z4fqCoY= X-Received: by 2002:a17:902:b94c:b0:192:b866:ab3d with SMTP id h12-20020a170902b94c00b00192b866ab3dmr1560203pls.99.1673152150549; Sat, 07 Jan 2023 20:29:10 -0800 (PST) MIME-Version: 1.0 References: In-Reply-To: Reply-To: linuxtechguy@gmail.com From: Jim Date: Sat, 7 Jan 2023 22:28:56 -0600 Message-ID: Subject: Re: read with redirected stdin To: Pier Paolo Grassi Cc: zsh Content-Type: multipart/mixed; boundary="00000000000096d40b05f1b917b5" X-Seq: 28624 Archived-At: X-Loop: zsh-users@zsh.org Errors-To: zsh-users-owner@zsh.org Precedence: list Precedence: bulk Sender: zsh-users-request@zsh.org X-no-archive: yes List-Id: List-Help: , List-Subscribe: , List-Unsubscribe: , List-Post: List-Owner: List-Archive: --00000000000096d40b05f1b917b5 Content-Type: multipart/alternative; boundary="00000000000096d40705f1b917b3" --00000000000096d40705f1b917b3 Content-Type: text/plain; charset="UTF-8" On Sat, Jan 7, 2023 at 11:23 AM Pier Paolo Grassi wrote: > Thanks, but i don't _always_ redirect stdin. > i wonder how is ps getting the tty (it displays an ? when there is no tty > for the process) > I suppose it uses /proc, but couldn't find a reference or the info > exploring the /proc fs by myself. > for now I am asking directly ps: > [[ "$(ps h -o tty $$)" != "?" ]] && ... > > Pier Paolo Grassi > > Hi, Don't really have an answer how ps gets its info but the attached script is something I have been working on. It uses the /proc file system directly to get info. It uses zstat to look for the tty info. If nothing is returned it substitutes '?". Some processes point to /dev/null. The script is still a work in progress. I was trying to get the same results as "ps -eHo uid=,pid=,ppid=,tty=,comm=" via a zsh script. This doesn't answer your original question, but may give you some insight into the /proc file system. Hope the script is helpful. Regards, Jim Murphy --00000000000096d40705f1b917b3 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable

On Sat, Jan 7, 2023 at 11:23 AM Pier Paol= o Grassi <pierpaolog@gmail.com> wrote:
Thanks, but i don't=C2=A0_always_ redirect stdin.
i wonder how is ps getting the tty (it displays an ? when there is= no tty for the process)
I suppose it uses /proc, but couldn'= t find a reference or the info exploring the /proc fs by myself.
= for now I am asking directly ps:
[[ "$(ps h -o tty $$)"= !=3D "?" ]] && ...
<= div dir=3D"ltr">

Pier Paolo Grassi





<= div>Jim Murphy

--00000000000096d40705f1b917b3-- --00000000000096d40b05f1b917b5 Content-Type: application/octet-stream; name=ps_eHo_via_zsh_script Content-Disposition: attachment; filename=ps_eHo_via_zsh_script Content-Transfer-Encoding: base64 Content-ID: X-Attachment-Id: f_lcmvejcw0 ZW11bGF0ZSAtTCB6c2gKc2V0b3B0IGV4dGVuZGVkZ2xvYgojIEZ1bmN0aW9uOiAgcHNfZUhvX3Zp YV96c2hfc2NyaXB0CiMgV0lQLCBzdGlsbCBuZWVkIHRvIGZpZ3VyZSBvdXQgaG93IHRvIG1ha2Ug YSB0cmVlKGZvcmVzdCkKICBbWyAtdiBtb2R1bGVzW3pzaC9zdGF0XSBdXSB8fCB6bW9kbG9hZCB6 c3RhdApsb2NhbCAgICAgRSBMIE0gTiBWCmxvY2FsIC1hICBBIEIgWCBZIFogUHMKbG9jYWwgLUEg IHByb2NfY29tbSBwcm9jX3R0eSBwcm9jX3BwaWQgcHJvY191aWQKUHM9KFBpZDogUFBpZDogTmFt ZTogVWlkOikgOyBQPSIkeyhqLnwuKVBzfSIKIyAicHMgLWVIbyB1aWQ9LHBpZD0scHBpZD0sdHR5 PSxjb21tPSIgLS0gInBzIiAgdnMgICJwcyB2aWEgenNoIHNoZWxsIgojIGlzc3VlOiAgbWFraW5n IGEgdHJlZShmb3Jlc3QpIGZvcm1hdHRlZCBvdXRwdXQgbGlrZSB0aGUgcHMgY29tbWFuZApBPSgv cHJvYy88LT4oL0ROKSkgOyBBPSgke0EjIyovfSkKZm9yIEUgKCRBKSB7CiAgW1sgISAtZCAvcHJv Yy8kRSBdXSAmJiB7IE49JHtBWyhpKSRFXX0gOyBbWyAkTiAtbGUgJCNBIF1dICYmIEFbTl09KCkg fSB9CmZvciBFICgkQSkgQis9KCR7KGYpIiQoPC9wcm9jLyRFL2NvbW0pIn0pIDsgTT0ke0FbJHtC WyhpKWZpcmVmb3gtZXNyXX1dfQpmb3IgRSAoJEEpIHsKICBCPSgkeyhNKSR7KGYpIiQoPC9wcm9j LyRFL3N0YXR1cykifTojKCR+UCkqfSkKICBaPSgkeyh6KUJbJHtCWyhpKVVpZDoqXX1dfSkgOyBb WyAkWlsyXSAtbmUgMCAmJiAkWlsyXSAtbmUgJFVJRCBdXSAmJiBjb250aW51ZQogIFo9KCR7KHop Qlske0JbKGkpUFBpZDoqXX1dfSkgIyBza2lwIGlmIHBwaWQgaXMgMgogICAgW1sgJFpbMl0gLWVx IDIgfHwgJFpbMl0gPT0gJE0gXV0gJiYgY29udGludWUgfHwgcHJvY19wcGlkWyRFXT0ke1pbMl19 CiAgWj0oJHs9Qlske0JbKGkpTmFtZToqXX1dfSkgOyBwcm9jX2NvbW1bJEVdPSR7WlsyLC0xXX0K ICBaPSgkeyh6KUJbJHtCWyhpKVVpZDoqXX1dfSkgIDsgcHJvY191aWRbJEVdPSR7WlsyXX0KICBW PSQoenN0YXQgK2xpbmsgL3Byb2MvJEUvZmQvMCAyPi9kZXYvbnVsbCkgXAogICAgcHJvY190dHlb JEVdPSR7JHske1Y6PVw/fSMvZGV2L30lOip9Cn0KTD0keyMkeyhPQHYpcHJvY190dHkvLz8vWH1b MV19CmZvciBFICgkeyhvbmspcHJvY19jb21tfSkgewogIHByaW50ZiAiJTVzICU1cyAlNXMgJS0k e0x9cyAlc1xuIiAkRSBcCiAgICAkcHJvY19wcGlkWyRFXSAkcHJvY191aWRbJEVdICRwcm9jX3R0 eVskRV0gJHByb2NfY29tbVskRV0KfQo= --00000000000096d40b05f1b917b5--