Path: csiph.com!news.redatomik.org!fdn.fr!proxad.net!feeder1-2.proxad.net!news.tele.dk!news.tele.dk!small.news.tele.dk!usenet.stanford.edu!not-for-mail From: John Cowan Newsgroups: gnu.utils.bug Subject: Re: Bug of grep -E Date: Wed, 6 Dec 2017 10:45:25 -0500 Lines: 26 Approved: bug-gnu-utils@gnu.org Message-ID: References: NNTP-Posting-Host: lists.gnu.org Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" X-Trace: usenet.stanford.edu 1512575150 19650 208.118.235.17 (6 Dec 2017 15:45:50 GMT) X-Complaints-To: action@cs.stanford.edu Cc: bug-gnu-utils To: iPack <2741547153@qq.com> Envelope-to: bug-gnu-utils@gnu.org DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ccil-org.20150623.gappssmtp.com; s=20150623; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc; bh=cNaxJ26DfLfuC68ywMLL/FwwQq04yNrLK8DvwCPD7sI=; b=k8oF+b53Xpikl0JajgBiQDj8rmakbpFhRMuPtlvhRM/lPnIpCmtwtWc4eLeAvP0Htx yj8Zb9JY4mr41zH3et0ZHWHyuCfEDifyi2erMFru8rPLxQ9PIAorh2xE7VMy7HqUPyOm sxm8eKTawoQ1CAGw3Y7PBSAFZi2EEFrYkMPMuq2umGWS3hTfoWr8/wpEum43fVXrq8xa deOUxRqg3bw2rp80Gkxc/n/65n9wndb+ayvLt9IDCKNUnkIDTX0QbICYhfmH9PkALiSv gKqMY8athR8jBGrDUq74bIJQWjDzT2+YKOrxnyVh5IAnMbHNFGgDUrGxIc8GGHwLe5tL q8pQ== 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=cNaxJ26DfLfuC68ywMLL/FwwQq04yNrLK8DvwCPD7sI=; b=mbfrKQAiqMvT8onqpl0V0uTvvqWEDAXFC/Nhl8e/SywnpnB6gwcBopcQ4kBN2+yPox ceBoj+coKq09UianPNrSYvHaDnMH6XWS+gQs8BZWIraDd5hFoWYa6HuDg0NgDMUkKy3n Pv6LolJs0bfVpawmRpHEkBklO6Vl+UraBBhEU7N2967eof0x9m37QQhuWsV04C6jqqUF R85+4fSJ/BIfS/kjuJ1Q15z8xGidwREUoWEERnNVbOuUmqMNEuVecw9XSYmgs2z7B4ia PdfJGVqvdnjCqYo2zCyRaBabka8BBfjBJvhHri6/p5uod2ELtthxsm1eafw/p6mGeSTh zWYA== X-Gm-Message-State: AJaThX61NgHxykQiL+brr5UmsOFphiVZc47lOnrFrEMnYBRrkQV+N+uf sAOpg4k/ahTYkXjlNHeI3a0mQifZSHUd+ruoknPfKQ== X-Google-Smtp-Source: AGs4zMYg/47Tqc0/si1gUp5cbkNhpJ10Nyvp6DdgTUeIbn0VOYYXtipq84RFXR61bXECJ5Xceeo1+8s2y+fRrTyoe0U= X-Received: by 10.157.35.42 with SMTP id j39mr22030122otb.167.1512575145719; Wed, 06 Dec 2017 07:45:45 -0800 (PST) In-Reply-To: X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 2607:f8b0:4003:c0f::22f X-Content-Filtered-By: Mailman/MimeDel 2.1.21 X-BeenThere: bug-gnu-utils@gnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: Bug reports for the GNU utilities List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Xref: csiph.com gnu.utils.bug:2225 Backslash is not an escape in character classes. The only way to get a - in a character class is to make sure it is at the end or the beginning. So in your second pattern, the sequence \-% means "every character from backslash to percent', which is no characters at all. On Wed, Dec 6, 2017 at 10:02 AM, iPack <2741547153@qq.com> wrote: > [urain39@urain39-pc ~]$ cat test > https://konachan.com/image/a4ff5caad2fa35faa2271df9badacd > 35/Konachan.com%20-%20255941%20blush%20brown_eyes%20crying% > 20fate_kaleid_liner_prisma_illya%20fate_%28series%29% > 20japanese_clothes%20kimono%20long_hair%20miyu_edelfelt% > 20purple_hair%20tagme_%28artist%29%20tears.jpg > > [urain39@urain39-pc ~]$ cat test | grep -Eo '[0-9a-f]{32}/[0-9A-Za-z%_\.\- > ]+' > a4ff5caad2fa35faa2271df9badacd35/Konachan.com%20-%20255941% > 20blush%20brown_eyes%20crying%20fate_kaleid_liner_prisma_ > illya%20fate_%28series%29%20japanese_clothes%20kimono% > 20long_hair%20miyu_edelfelt%20purple_hair%20tagme_%28artist%29%20tears.jpg > > [urain39@urain39-pc ~]$ cat test | grep -Eo '[0-9a-f]{32}/[0-9A-Za-z\-%_\. > ]+' > a4ff5caad2fa35faa2271df9badacd35/Konachan.com%20 > > It is bug ? or just my syntax error ?