From debbugs-submit-bounces@debbugs.gnu.org Fri Apr 14 02:40:11 2017 Received: (at submit) by debbugs.gnu.org; 14 Apr 2017 06:40:11 +0000 Received: from localhost ([127.0.0.1]:46362 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1cyutv-0006Ig-3p for submit@debbugs.gnu.org; Fri, 14 Apr 2017 02:40:11 -0400 Received: from eggs.gnu.org ([208.118.235.92]:45562) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1cyuqq-0006Di-LV for submit@debbugs.gnu.org; Fri, 14 Apr 2017 02:37:00 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cyuqk-00022R-NO for submit@debbugs.gnu.org; Fri, 14 Apr 2017 02:36:55 -0400 X-Spam-Checker-Version: SpamAssassin 3.3.2 (2011-06-06) on eggs.gnu.org X-Spam-Level: X-Spam-Status: No, score=0.0 required=5.0 tests=BAYES_20,FREEMAIL_FROM, HTML_MESSAGE,T_DKIM_INVALID autolearn=disabled version=3.3.2 Received: from lists.gnu.org ([2001:4830:134:3::11]:52372) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1cyuqk-00022L-LB for submit@debbugs.gnu.org; Fri, 14 Apr 2017 02:36:54 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:36508) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cyuqj-0004eh-K5 for bug-coreutils@gnu.org; Fri, 14 Apr 2017 02:36:54 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cyuqi-00020t-5U for bug-coreutils@gnu.org; Fri, 14 Apr 2017 02:36:52 -0400 Received: from mail-lf0-x236.google.com ([2a00:1450:4010:c07::236]:33354) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1cyuqh-0001zt-UY for bug-coreutils@gnu.org; Fri, 14 Apr 2017 02:36:52 -0400 Received: by mail-lf0-x236.google.com with SMTP id h125so38634678lfe.0 for ; Thu, 13 Apr 2017 23:36:51 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:from:date:message-id:subject:to; bh=9+nRDw2Ah/EPxM1e3BnoZjF7aWJ4iPRu/QQQpoWqQWs=; b=ZfRNzrczEsrVIMinpu+4ifAp1ITQDzBXPdh/ThZTIWdVN2wJe0UAisa95LMkyCX63l FxLNjsl8LiKNk6rD/aq01G3vG4qBmFfmX2RPj/j+U03tCvyvWr7Fe+OvKF+Rc0SyIlfm j4WMe5GhHOFIbtlJVQ0cRRqG8nkr4WgwojnxT1HEwA1GHuZGRqpRbXu9BeuY+sQmtMBj o892JLtzi1fvl8IdOCHLjwWVSy/N6WtPoZ8TZqAbB8Z51tmTLNwo4R9zmPwojbyraLUn ATsL1GDzMpMxEaieY/DP8JINPw64hbdQn1OtAwG++XEpZcneiSihtjYQJpiuvwYtbd1L 4HiA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:from:date:message-id:subject:to; bh=9+nRDw2Ah/EPxM1e3BnoZjF7aWJ4iPRu/QQQpoWqQWs=; b=VBwtayMIaAGMBWQq8qgsjpkKFBz6U4B4PEZzoo2H17Vq/c5l+YLk/gWU28JswFInjo gT9Iup513iDLUeiAeP+PXl323qg9BZaF94r8RF0glh73uMGs2YcTJS5CWE631+X6K8MF MgtVbwTUscyZ7m3YZcdVGtPD+4Wcj4GDzJPWW4GayQ8G5Zx1DMUa0gasqmufjCq7LWz+ 0/uX+/7nu2xI+I5yrmCWPWuDLcFqaY2LwNYajdJbTjdSHA16hUU5FzOzvz/J94jbFN0y VC6A+f/DbqX1gohNZKlMciFaCS2mOKSxZYwvK5nbzWuNh9f90dtmjQ4BdNUtfxD822Lf prvQ== X-Gm-Message-State: AN3rC/7ujx835Q32IGCzuuXEkcSJZ7gXQWSpsBKiRzS4T0yfmmhmwGNr NGfpXRt1tXgyXUTjPokyn2qZ0orpUIgy X-Received: by 10.25.56.22 with SMTP id f22mr2482532lfa.83.1492151809882; Thu, 13 Apr 2017 23:36:49 -0700 (PDT) MIME-Version: 1.0 Received: by 10.25.203.70 with HTTP; Thu, 13 Apr 2017 23:36:49 -0700 (PDT) From: Edmond Yuen Date: Fri, 14 Apr 2017 14:36:49 +0800 Message-ID: Subject: date and echo using with underscore To: bug-coreutils@gnu.org Content-Type: multipart/alternative; boundary=f403045ea0aa94425e054d1aaa0b X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.6.x X-Received-From: 2001:4830:134:3::11 X-Spam-Score: -4.0 (----) X-Debbugs-Envelope-To: submit X-Mailman-Approved-At: Fri, 14 Apr 2017 02:40:10 -0400 X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: debbugs-submit-bounces@debbugs.gnu.org Sender: "Debbugs-submit" X-Spam-Score: -4.0 (----) --f403045ea0aa94425e054d1aaa0b Content-Type: text/plain; charset=UTF-8 Please verify the script below: #/bin/bash D=`date +%Y%m%d` i="someparameter" echo $D_$i echo $D\_$i echo $D echo $i echo _ // my system is debian with coreutils 8.26-3 // // db=`date -d "-1day" +%Y%m%d` // i="0" This is the result from my system ~$ echo "$db_$i" 0 ~$ echo "$db\_$i" 20170413\_0 ~$ echo "$db$i" 201704130 Thank you! --f403045ea0aa94425e054d1aaa0b Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable
Please verify the script below:
#/bin/bash

D=3D`date +%Y%m%d`
i=3D"somepa= rameter"

echo $D_$i
echo $D\_$i
echo $D
echo $i
echo _



<= br>
//=C2=A0=C2=A0 my system is debian with coreutils 8.26-3
<= /div>
//
//=C2=A0=C2=A0 db=3D`date -d "-1day" +%Y%m%d`
=
//=C2=A0=C2=A0 i=3D"0"
This is the resul= t from my system

~$ echo "$db_$i"
0
~$ ec= ho "$db\_$i"
20170413\_0
~$ echo "$db$i"
20170= 4130

Thank you!
--f403045ea0aa94425e054d1aaa0b-- From debbugs-submit-bounces@debbugs.gnu.org Fri Apr 14 11:14:20 2017 Received: (at 26491) by debbugs.gnu.org; 14 Apr 2017 15:14:20 +0000 Received: from localhost ([127.0.0.1]:47343 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1cz2vT-0003lY-Pk for submit@debbugs.gnu.org; Fri, 14 Apr 2017 11:14:19 -0400 Received: from vhrz24.hrz.uni-marburg.de ([137.248.1.34]:50153) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1cz2vR-0003lQ-D6 for 26491@debbugs.gnu.org; Fri, 14 Apr 2017 11:14:17 -0400 Received: from [10.47.221.243] (tmo-106-15.customers.d1-online.com [80.187.106.15]) (authenticated bits=0) by vhrz24.HRZ.Uni-Marburg.DE (8.14.4/8.14.4/Debian-8+deb8u1) with ESMTP id v3EFE87v056759 (version=TLSv1/SSLv3 cipher=ECDHE-RSA-AES256-SHA bits=256 verify=NOT); Fri, 14 Apr 2017 17:14:10 +0200 References: Mime-Version: 1.0 (1.0) In-Reply-To: Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-Id: <56D55ED7-E63B-4CE2-8F4B-18C862479EDD@staff.uni-marburg.de> X-Mailer: iPhone Mail (13G36) From: Reuti Subject: Re: bug#26491: date and echo using with underscore Date: Fri, 14 Apr 2017 17:14:07 +0200 To: Edmond Yuen X-Null-Tag: e3634c889a6bf4a9c820a841ebc3bb64 X-UniMR-MailScanner-Information: see http://www.uni-marburg.de/hrz/internet/mail/spam/ X-UniMR-MailScanner-ID: v3EFE87v056759 X-UniMR-MailScanner: Found to be clean X-UniMR-MailScanner-From: reuti@staff.uni-marburg.de X-Spam-Score: -2.3 (--) X-Debbugs-Envelope-To: 26491 Cc: 26491@debbugs.gnu.org X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: debbugs-submit-bounces@debbugs.gnu.org Sender: "Debbugs-submit" X-Spam-Score: -2.3 (--) Hi, > Am 14.04.2017 um 08:36 schrieb Edmond Yuen : > > Please verify the script below: > > #/bin/bash > > D=`date +%Y%m%d` > i="someparameter" > > echo $D_$i > echo $D\_$i > echo $D > echo $i > echo _ > > > > > // my system is debian with coreutils 8.26-3 > // > // db=`date -d "-1day" +%Y%m%d` > // i="0" > This is the result from my system > > ~$ echo "$db_$i" > 0 > ~$ echo "$db\_$i" > 20170413\_0 > ~$ echo "$db$i" > 201704130 The syntax is to use curly braces to limit the name of the varable: echo "${db}_${i}" -- Reuti From debbugs-submit-bounces@debbugs.gnu.org Fri Apr 14 11:28:54 2017 Received: (at 26491) by debbugs.gnu.org; 14 Apr 2017 15:28:55 +0000 Received: from localhost ([127.0.0.1]:47357 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1cz39a-00046W-LD for submit@debbugs.gnu.org; Fri, 14 Apr 2017 11:28:54 -0400 Received: from mail-wm0-f43.google.com ([74.125.82.43]:37474) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1cyw0F-000809-0t for 26491@debbugs.gnu.org; Fri, 14 Apr 2017 03:50:47 -0400 Received: by mail-wm0-f43.google.com with SMTP id u2so60781674wmu.0 for <26491@debbugs.gnu.org>; Fri, 14 Apr 2017 00:50:46 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc; bh=zvoBduTsVAoY7FmTidbgeCaq2o567yLjfdRMXxvhX90=; b=hNMUgqWx7iX+R4Z69SEJCHlYFvx/0F8pC70tCTNUZwT+jFGGO2Sg9XYvLdgcYnjX9u oVEeB7azEn6vF2h4KipUjPnaaN610ywMDTdlDAYnXUwUJrPdGlWB+WS9oPZXUYEzlNnK 77iCE5DzG7ZDQKSoZu33gqDzgt6KYYoL2pEa71X7lYrpBz0aOtKzyPJ2fsipUs8WqMUW wZexpoeQ0VgbTH677mbu1Ar0RELFcYjTdN0+UvjjILw60WLzFO3J/CcGmHdY2xqFqaeJ otgab/R7bymu5Ppyi3CXQxBG/MfAajRFKzWwcaizbHzM2D2yafG6D5vmZSHmFx5SFbZv eikA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:in-reply-to:references:from:date :message-id:subject:to:cc; bh=zvoBduTsVAoY7FmTidbgeCaq2o567yLjfdRMXxvhX90=; b=Qu/5WKXUqKzPvTpnnnUSnZXlVHvVfFrn+b3qP666a9n+Jcfm5GYxJL6qpd28GkOPNV kv2tcLxV9VSphDHUbhKiTtxuPMO6aSdgNyd0Xrjxmb0vgaykhKxD0lJ7WxkD7iocqkYf kOZX14mPcjoSN6wNqbX7025jw6ER7mnLKUP42zI/2BDuav+YzxxfhHxcTBMf8zIkVU/h /tEmp4O+T0SKKMNH69Ti3fYaq4EAn2owJ1ksIdYg6iyQiHtU8Zr2iZ1QN70Ziz4hM4Xs ZLIqkjTb4V/4jwCVaQTFjwJBjv1W2R1R0IM+FdwcIA8szGwcMlpRQW/p1j71JngOLBWl wLYQ== X-Gm-Message-State: AN3rC/6gbQ8LMqf5xbBt1yH17kIVxT3JfjX27QLGjcXfH3ydTODOGmeS zHQpHpP6e7zOYEsaftXvAT04+2ODSA== X-Received: by 10.28.146.12 with SMTP id u12mr6854972wmd.142.1492156241217; Fri, 14 Apr 2017 00:50:41 -0700 (PDT) MIME-Version: 1.0 Received: by 10.28.23.195 with HTTP; Fri, 14 Apr 2017 00:50:39 -0700 (PDT) Received: by 10.28.23.195 with HTTP; Fri, 14 Apr 2017 00:50:39 -0700 (PDT) In-Reply-To: References: From: =?UTF-8?Q?Martin_M=C3=B8ller_Skarbiniks_Pedersen?= Date: Fri, 14 Apr 2017 09:50:39 +0200 Message-ID: Subject: Re: bug#26491: date and echo using with underscore To: Edmond Yuen Content-Type: multipart/alternative; boundary=001a114434a0b50e24054d1bb2bd X-Spam-Score: -0.0 (/) X-Debbugs-Envelope-To: 26491 X-Mailman-Approved-At: Fri, 14 Apr 2017 11:28:53 -0400 Cc: 26491@debbugs.gnu.org X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: debbugs-submit-bounces@debbugs.gnu.org Sender: "Debbugs-submit" X-Spam-Score: -0.0 (/) --001a114434a0b50e24054d1bb2bd Content-Type: text/plain; charset=UTF-8 On Apr 14, 2017 08:41, "Edmond Yuen" wrote: Please verify the script below: #/bin/bash D=`date +%Y%m%d` i="someparameter" echo $D_$i echo $D\_$i echo $D echo $i echo _ // my system is debian with coreutils 8.26-3 // // db=`date -d "-1day" +%Y%m%d` // i="0" This is the result from my system ~$ echo "$db_$i" 0 ~$ echo "$db\_$i" 20170413\_0 ~$ echo "$db$i" 201704130 This output looks ok to me. Do you expect something different? and why? --001a114434a0b50e24054d1bb2bd Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable


On Apr 14, 2017 08:41, "Edmond Yuen" <lordedmond@gmail.com> wrote:
Please verify the script below:

#/bin/bash

D=3D`date +%Y%m%d`
i=3D"someparameter"

echo $D_$i
echo $D\_$i
echo $D
echo $i
echo _




//=C2=A0 =C2=A0my system is debian with coreutils 8.26-3
//
//=C2=A0 =C2=A0db=3D`date -d "-1day" +%Y%m%d`
//=C2=A0 =C2=A0i=3D"0"
This is the result from my system

~$ echo "$db_$i"
0
~$ echo "$db\_$i"
20170413\_0
~$ echo "$db$i"
201704130

This output looks ok to me.=C2=A0
Do = you expect something different? and why?

<= div dir=3D"auto">

--001a114434a0b50e24054d1bb2bd-- From debbugs-submit-bounces@debbugs.gnu.org Fri Apr 14 11:50:23 2017 Received: (at 26491) by debbugs.gnu.org; 14 Apr 2017 15:50:23 +0000 Received: from localhost ([127.0.0.1]:47364 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1cz3UM-0004af-Q7 for submit@debbugs.gnu.org; Fri, 14 Apr 2017 11:50:23 -0400 Received: from mail-qk0-f169.google.com ([209.85.220.169]:36033) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1cz3UJ-0004aM-Vn; Fri, 14 Apr 2017 11:50:20 -0400 Received: by mail-qk0-f169.google.com with SMTP id d131so70238683qkc.3; Fri, 14 Apr 2017 08:50:19 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:to:references:from:message-id:date:user-agent:mime-version :in-reply-to:content-transfer-encoding; bh=vVGZvManRLPc4ZL0UrEktPvRMaBG+S6NXdyc8WjFxhc=; b=kUKCbhIGhdrfCM7d+zwyCl/CZeaNd2sNRQECedH4zOkE5gxADVzhRz/F/nrZR06wud R18A+APMP6Il3BDFQg+svYk0Oo732d81k6gJlyzfcQJZss9UHrsEHs5F3RtXUlUbk04y 3QBxfmGdrLcqIZTfG85GmfGVjX4CxeSO52mvO5pPVdjMBBnlhoKlVdxdrheSyyN4/Jh8 km0Hnp8ehAumWDwPcSB1jQZvRN4g5fnr7cpAM0yxmcPeLpQOTPN+Lh+kMJbGjUFhzH3p apzhYC8O/hl4sRcSJf6Q0ajm1TYfpGIOv1piDoYPFKMNabVpPmh907CkNJkLKHGzcoVW XyhQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-transfer-encoding; bh=vVGZvManRLPc4ZL0UrEktPvRMaBG+S6NXdyc8WjFxhc=; b=qF0qLJng5lZW+xIAyEGYrEoaFMeUma1Wdfce3M1u+Q0w430gJMUlebva4hoRTksa9v Sf+xw1ytIrj33y5HXtqJqgVxUPYrBNfQio3bw5WQtEBInPHI+P5D2MtvDE+nJASYI6Bs vaOzf9aEDhtL4Wc+F7Xq2M+qxlsLvyS5Xv08SwMnpMunyQs/q1ttK7zTF1jtYy1pkjGP 2SFpswb66b2/4leGij9lB3vrwbqmPyODDztkLLqvKwXWW9jdO7GqDCrDsrxbeBSmmx8X EoofzuUx0KELEJK7O8pWJabpqCcSxNxz9q8llpiOky4uL80de4IhanFLuK0lkjwzO4B+ 4YSQ== X-Gm-Message-State: AN3rC/5Cf+BcdG7Elq2KwMMLukr1uJAvsGjo9Vs229eaVicDMPdRiAja ghdNZqez7XCoLA== X-Received: by 10.55.188.68 with SMTP id m65mr8003151qkf.152.1492185014193; Fri, 14 Apr 2017 08:50:14 -0700 (PDT) Received: from disco.erlich.nygenome.org ([69.74.14.178]) by smtp.gmail.com with ESMTPSA id k40sm137151qtf.27.2017.04.14.08.50.13 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 14 Apr 2017 08:50:13 -0700 (PDT) Subject: Re: bug#26491: date and echo using with underscore To: Edmond Yuen , 26491@debbugs.gnu.org References: From: Assaf Gordon Message-ID: <5b8c9b36-af4d-1c5d-8c33-ba8da43fdde9@gmail.com> Date: Fri, 14 Apr 2017 11:50:12 -0400 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.8.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-Spam-Score: 0.5 (/) X-Debbugs-Envelope-To: 26491 X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: debbugs-submit-bounces@debbugs.gnu.org Sender: "Debbugs-submit" X-Spam-Score: 0.5 (/) tag 26491 notabug close 26491 stop Hello Edmond, On 04/14/2017 02:36 AM, Edmond Yuen wrote: > echo $D_$i As others have replied (and thanks to all who replied), an underscore character is valid part of a shell variable, thus the shell tries to use the content of the variable "D_" - which is empty. This is part of the POSIX standard for shell variable expansion. Specifically here: http://pubs.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html#tag_02_06_02 2.6.2 Parameter Expansion ... "If the parameter name or symbol is not enclosed in braces, the expansion shall use the longest valid name (see the Base Definitions volume of IEEE Std 1003.1-2001, Section 3.230, Name), whether or not the symbol represented by that name exists." And "Section 3.230, Name" says: http://pubs.opengroup.org/onlinepubs/009695399/basedefs/xbd_chap03.html#tag_03_230 "In the shell command language, a word consisting solely of underscores, digits, and alphabetics from the portable character set." This is not a bug in date or echo (or a bug at all), and I'm closing this bug. Discussion can continue by replying to this thread. Lastly, To detect and fail early when undefined variables are used, you can optionally enable "-u" in your shell scripts: #!/bin/sh set -u A=hello echo A=$A echo A_=$A_ And the shell will terminate the script with: $ ./test.sh A=hello test.sh: 5: test.sh: A_: parameter not set regards, - assaf From unknown Thu Sep 11 23:31:37 2025 Received: (at fakecontrol) by fakecontrolmessage; To: internal_control@debbugs.gnu.org From: Debbugs Internal Request Subject: Internal Control Message-Id: bug archived. Date: Sat, 13 May 2017 11:24:05 +0000 User-Agent: Fakemail v42.6.9 # This is a fake control message. # # The action: # bug archived. thanks # This fakemail brought to you by your local debbugs # administrator