X-Recipient: archive-cygwin AT delorie DOT com X-SWARE-Spam-Status: No, hits=3.1 required=5.0 tests=AWL,BAYES_50,FREEMAIL_FROM,KAM_THEBAT X-Spam-Check-By: sourceware.org Date: Mon, 31 May 2010 03:35:19 +0400 From: Andrey Repin Reply-To: Andrey Repin Message-ID: <1656998784.20100531033519@mtu-net.ru> To: Christopher Faylor Subject: Re: Reading /proc/registry/... returns extra char In-Reply-To: <20100530055757.GA3251@trixie.casa.cgf.cx> References: <20100513181249 DOT GE13784 AT cupro DOT opengvs DOT com> <2BF01EB27B56CC478AD6E5A0A28931F2F01D44 AT A1DAL1SWPES19MB DOT ams DOT acs-inc DOT net> <20100526114733 DOT GG10652 AT calimero DOT vinschen DOT de> <1254830174 DOT 20100526174227 AT mtu-net DOT ru> <20100526143428 DOT GN10652 AT calimero DOT vinschen DOT de> <326990670 DOT 20100530001515 AT mtu-net DOT ru> <20100530055757 DOT GA3251 AT trixie DOT casa DOT cgf DOT cx> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-IsSubscribed: yes Mailing-List: contact cygwin-help AT cygwin DOT com; run by ezmlm Precedence: bulk List-Id: List-Unsubscribe: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: cygwin-owner AT cygwin DOT com Mail-Followup-To: cygwin AT cygwin DOT com Delivered-To: mailing list cygwin AT cygwin DOT com Greetings, Christopher Faylor! >>>> >> > $ cat >a.dat >>>> >> > /proc/registry/HKEY_LOCAL_MACHINE/SYSTEM/CurrentControlSet/Control/Syst >>>> >> > emBootDevice >>>> >>>> > This trailing NUL character was always there, already with Cygwin 1.5. >>>> > It's part of the file content. If strings are stored with a trailing >>>> > NUL in a file, you don't want Cygwin to remove it for you, right? >>>> >>>> Wrong. The training NULL is a string value terminator for REG_SZ variables, >>>> also a string separator for REG_MULTI_SZ ones. (Which ends with a spare NULL) >>>> It must not be exposed to the user. >> >>> I disagree. When you're using tools like regtool, you're right. But >>> when accessing the registry as *files* via the virtual /proc filesystem, >>> you want the file content. >> >>Yep. And I certainly not expect the NULL in text files. You know, not every >>console program is binary-safe when working with STDIO? Not even cygwin, as we >>can see in this thread. >> >>> And the file contains the trailing NUL in REG_SZ and REG_EXPAND_SZ values, >>> and multiple NULs in REG_MULTI_SZ values. >> >>That's right and true, when you're working with interface directly, but... all >>the programs I've used in the past, and all the interfaces, they do not expose >>trailing NULL to the client application. >>In this case, /proc/registry is an interface, but cat is the application. > NAME > cat - concatenate files and print on the standard output > I don't see anything in cat's description which claims it should know > that some files are special and should be handled differently. I didn't said about cat, but rather about file it reading from. >>> What do you suppose Cygwin should do with the NULs in REG_MULTI_SZ values? >>> Just remove them? >> >>Convert them to appropriate EOL sequences. And back to NULL's on write. As per >>definition of a text as "multiple strings". >>You don't need to argue over it, just document it properly :) > Converting a NUL to a EOL would be very strange behavior. Strange? I don't think so. I expect text data from text file. Not binary stream. > I don't think you really know what you're asking for. I know. Look at windows own regedit and Registry Browser FAR plugin as two examples. They do such two-way conversion transparently for user. -- WBR, Andrey Repin (anrdaemon AT freemail DOT ru) 31.05.2010, <3:29> Sorry for my terrible english... -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple