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,MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED, UNPARSEABLE_RELAY autolearn=ham autolearn_force=no version=3.4.4 Received: (qmail 14396 invoked from network); 31 Aug 2021 18:13:53 -0000 Received: from zero.zsh.org (2a02:898:31:0:48:4558:7a:7368) by inbox.vuxu.org with ESMTPUTF8; 31 Aug 2021 18:13:53 -0000 ARC-Seal: i=1; cv=none; a=rsa-sha256; d=zsh.org; s=rsa-20210803; t=1630433633; b=JhI3C5ix3aS9SNMhnkPhjXUGzuc+x+wPe8MweML63NEdU1/3Qi1Z+aBXfesk92gkdfmBzUJS2p TT5TVDxaAuFN1wmfdnYx08NBeXBiNYHmQIS4BXlhIEDbCJS6kkqynAALIWQ2tbyPnl1ZxXx2NK 8aHEOaDdnXvo6Ynb//6ZULVoJNNb4/EWnR6mljz2AyvZTTuD9gA1x26XYSTO1KMVUZr0sRDkdw Nq5+JM6ZlVxul4BL84tJU+hA55QOY87IKJWAcJPY4dZW9isKXMH6QVYMcXCQF/xsv+jwY979pq znwsSnpEsjU7uMnEZYzxb+Cjknk08bJaNpv9rrnR9iKfYQ==; ARC-Authentication-Results: i=1; zsh.org; iprev=pass (mail-qk1-f176.google.com) smtp.remote-ip=209.85.222.176; dkim=pass header.d=gmail.com header.s=20161025 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=1630433633; bh=jtpB1LzI2aJKNkVge3TKxThhbxZMWAkgXftxU7B1Jqg=; 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:In-Reply-To: References:MIME-Version:DKIM-Signature:DKIM-Signature; b=ZFPzOdnz9//L8K1DmeGx+Zl2YAQmHYBPYoFVKUb/LQiMzN0E93p6yr+QIp4Pkn9ReP3yV7FEUQ GjrcJN3OhOcK/I9V3QvFz256Qt5gMjVVKkXCz9PlAsVFjkmpRgnuLtc9uBh6M8zNeYsEyQWtWn EG6tQJVJ9BWOwpbGh8CWR4uIffYpoNELTG9hYgXQF/UXflFBWXSSUeJH3vXhTZy+nOBRTOvRHC dUsBnNOqrS1yQd4IMbmOlm0x8Q/n3NxSv8ndW1BeE3LPUzjNP+FCu+J2Wb2LuJzv8auPhnOiXP wUO57XXQ4LErNxi4gm0T2tx1wE2n8T3t6HV6rPSvfxJ4Gw==; 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:In-Reply-To:References:MIME-Version:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID; bh=HW6jvJa8e5xPX0Hk8cC9NAGvbtRYPqABJZ4VZfM4dsg=; b=mm7fsrlb+oPZ7JhsXU1AP44OQT Rybs+3muC4MPiWe5pvLuFNLEqFDjIxfDJck/jKWC7awze3R7E6R4hzWxRgFyzhQouegLhjmZgSQ08 XVr3oN2ldi52T1PZa9q+p5+m4Ybv6IrubzYl4pNDJOM/tcDpfOWVItEAJ/gHFjNxHl31dF6b9A+jT BV2yC6OvoKgkV3p17cWpeh8VARiIjeQQmnqKIdMGl4zid8MLU23gZXz6qn3vCGOE266nqAUxFcu/6 osb2y/zLpIcMmJGZBPd7Y5pQOWksTd/kJ4se3zXZMWQxllgKGMpRLG0vdBix5mhXJjGiwx+y5sShz sV5skAtQ==; Received: from authenticated user by zero.zsh.org with local id 1mL8Gf-000D7h-H8; Tue, 31 Aug 2021 18:13:53 +0000 Authentication-Results: zsh.org; iprev=pass (mail-qk1-f176.google.com) smtp.remote-ip=209.85.222.176; dkim=pass header.d=gmail.com header.s=20161025 header.a=rsa-sha256; dmarc=pass header.from=gmail.com; arc=none Received: from mail-qk1-f176.google.com ([209.85.222.176]:43669) by zero.zsh.org with esmtps (TLS1.3:TLS_AES_128_GCM_SHA256:128) id 1mL8El-000CKA-0p; Tue, 31 Aug 2021 18:11:55 +0000 Received: by mail-qk1-f176.google.com with SMTP id ay33so164617qkb.10 for ; Tue, 31 Aug 2021 11:11:54 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=HW6jvJa8e5xPX0Hk8cC9NAGvbtRYPqABJZ4VZfM4dsg=; b=Riyx4vjaoF3aXrCU7wQ9zlUtbv36nbKO8sP9sFBCSoNKlS3Ei+UiAFmXztrZTXOgRF w9Blcdbn2jS5OzYoV7RauL/cU5N1duypBBSWa6+r6262idaSfMWrGznKtJ1dkZwpmboI b9Ry6A2e5N0lCse4aXgTIZOHAHvvVPtI9giTpUtzUGJDZy8oPate+rfpKj2NrELsOCYx cf+w/7sKkw0KRn5/ULXl5YiwuqkLt7Ved3FsZ0jxW/3wztO6i/GLjArEBV2m/ufJx7Nf iHfXBaz93XRLPizPhCP1t+0jS/IERZcUkLmMo4GTFTyk4Jkbmu+yCjzNtzMLKPE+sbJk LUbw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=HW6jvJa8e5xPX0Hk8cC9NAGvbtRYPqABJZ4VZfM4dsg=; b=gUIUSLhJytJFQFyJkYdqo3USE3xoG1G2DAKGyfjF6Httn9f6m5Gk49p8rXOZt2VmnS 3KAioVwvTfKqRuVlhwqMOKSs2Frfz32nw57WD/EEybbgijqU5Z9wp2JOjJ0ErrRy4lw4 qtr+Td1lTO9ZAVMokG3mqusATLpcXVke5oGTDPQoxUaXo1BExyWnfvIRi7IVtSG7APWN a4HAqettRJXne6vgseV30oqkBOpY3psAYzwpvpFN5Ql1zFLL2z/GHllta7kxGpjf906R n7mhRL+vXkxEVn4P81XN02iORoRgDsFDTemNYgWXreWeztXmtL37IwRwARehDlpOTV5P tBfg== X-Gm-Message-State: AOAM531sBnIXoxoufjEBKkwewL201V4UmpYl/XwJdmArhvvMjhPV9MAr 6Xke3tMoYmU+BZ1vRY6EA3uze89vOxMDBinn2ZabAh/nSLk= X-Google-Smtp-Source: ABdhPJyEPqxj77PX14qOMi7Zutn11lkYYJNxz+VeC7Euw5fvNXkhMTiYf3w7RtgYUX7aebeCJBj5f95RX2VrzMDqr0E= X-Received: by 2002:a05:620a:1909:: with SMTP id bj9mr4316752qkb.435.1630433514085; Tue, 31 Aug 2021 11:11:54 -0700 (PDT) MIME-Version: 1.0 References: In-Reply-To: From: Roman Perepelitsa Date: Tue, 31 Aug 2021 20:11:43 +0200 Message-ID: Subject: Re: autoload variables To: Anthony Fletcher Cc: Zsh Users Content-Type: text/plain; charset="UTF-8" X-Seq: 27026 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: On Tue, Aug 31, 2021 at 2:11 AM Anthony Fletcher wrote: > > I think that using a function that caches the value and then invoked via $(upif) is easiest. Something like > > upif () { export UPIF; echo ${UPIF:=$(ip r | ....) }} > tcpdump -i $(upif) ....... Assuming that you don't set UPIF manually anywhere else, this code is equivalent to this: upif() { ip r | ....} tcpdump -i $(upif) ....... That export and conditional assignment don't do anything because they are within a subshell. Anything you export there gets wiped out immediately and won't be used the next time you invoke $(upif). Roman.