On 9/4/16, Gene Pavlovsky wrote: > This issue never affected me personally, but it sounds like a serious > bug and I'm as glad as anybody that it's finally fixed. > However, having existing scripts suddenly breaking is not great. I'd > like to remind that I'm not the author of the script in question, > [AutoMySQLBackup](http://sourceforge.net/projects/automysqlbackup/). > If I put "| d2u" there I'll have to remember it and do it every time > automysqlbackup is updated ...
Right - updating something like automysqlbackup to add "| d2u" after every dos program call is a non-starter. But would putting the dos program inside a script that converted dos -> unix line endings work? eg - have a mysql script that comes before the windows version of mysql in your path that does something like /path/to/windows/version/of/mysql $@ | dos2unix > - or create and maintain a Cygwin package for this script. It seems to me that it isn't the script that's broken - it's the whole idea of having a dos program transparently integrate into an environment that expects unix line endings that's broken. So until there's a bash option that automatically translates '\r\n' line endings into '\n' line endings you're stuck doing some kind of work-around or using a cygwin version of mysql. Lee > And who knows how many other scripts might be broken, > I just didn't find it yet? > > Having a `read`-specific shell option telling read to treat `\r\n` > (and only `\r\n`, not \r followed by something else) same as `\n` > would be bad things to have? For me, this kind of option would be more > useful than the `igncr` crutch > Let me say it another way - in OOP programming, one of good practices > is Single Responsibility Principle - a class should be responsible for > only one feature/function, and that feature/function should be totally > encapsulated in that class. Similar to that, an option should be > responsible for one behavior. With this change to `read`, the `igncr` > shell option is starting to look like a kitchen sink... split it into > separate options, please! > I think making UNIX scripts work on Cygwin with no or minimum > modifications (or bug-hunting) should be one of high priorities, no? > If some scripts erroneously have CRLF line endings, it's easy to find > and `d2u` them, rather than using the `igncr` crutch, but with the > recent change to `read`, countless scripts might be broken in a > non-obvious way. Fixing them would require finding out they're broken, > in the first place. Imagine if I didn't set up my cron to e-mail me > the cron jobs output? My backup script would just stop working > silently, and some time later when I needed a recent backup, I would > find out there aren't any. There might be something else lurking that > I haven't found yet. Once a script, broken by this change to `read`, > is found, it must be checked thoroughly to find out where exactly is > the problem, where to put '| d2u', or maybe 'set -o igncr'. These > fixes must also be applied anytime a 3rd party script is updated. > Quite a lot of work! > Hope you will consider my point. > Regards, > Gene. > > On 30 August 2016 at 23:57, cyg Simple <cygsim...@gmail.com> wrote: >> On 8/30/2016 1:38 PM, Eric Blake wrote: >>> On 08/30/2016 12:04 PM, cyg Simple wrote: >>>> On 8/29/2016 2:30 PM, Eric Blake wrote: >>>>> >>>>> Simplest fix: >>>>> >>>>> read ... < <(mysql ... | dos2unix) >>>>> >>>> >>>> This will break when the data returned by mysql is supposed to contain >>>> \r. >>>> >>>>> There. Now you aren't feeding \r to read in the first place. >>>>> >>>> >>>> But you might want to feed \r to read. It isn't a fix, it is a >>>> potential work around dependent on the data set results. If a read >>>> that >>>> is supposed to be reading binary data doesn't pass all of the data to >>>> the routine then it is broken. >>> >>> Now we're talking past each other. >>> >>> That's what the recent bash fixed. 'read' in bash 3.2.42-4 was broken - >>> it corrupted binary data, with no recourse, by eating \r (and worse, by >>> sometimes eating the byte after \r). 'read' in bash 3.2.46-7 is fixed - >>> by default it is strictly binary (all bytes are read as-is, including >>> \r), but can also be switched to text mode (using 'igncr', all \r are >>> ignored). If you want to preserve mid-line \r but treat line endings of >>> \r\n as a single byte, then leave binary mode on and strip the line >>> endings via a separate tool like d2u (note, however, that it is very >>> rare to have data where mid-line \r is important but line-ending \r\n >>> should be treated as plain \n). >>> >>> I strongly think that using igncr is a crutch, and you normally >>> shouldn't use it; particularly not if you want to be portable to other >>> platforms. Instead, massaging your data through d2u is a great way to >>> be portable. But sometimes the ease of ignoring ALL \r is easier than >>> worrying about portability, so I keep the 'igncr' code in Cygwin. >>> >>> And it is only because the OP tried using 'igncr' in the first place >>> (whether or not it was actually needed) that we have now flushed out the >>> existence of a latent bug in the 'igncr' implementation that interacts >>> weirdly with $()\n in PS1. On that front, I'm still hoping to find time >>> to debug and/or for someone to post a patch. But whether PS1 behaves >>> weirdly under 'igncr' is orthogonal to my suggestion above - using >>> 'mysql|d2u' is a great way to avoid the need to worry about 'igncr'. >>> >> >> Thank you for the retort Eric. Happy to know that it is fixed which in >> the back of my mind I knew already. I can imagine data such as full >> message email or a small document data containing \r\n as valid data in >> the database field and if you use a line ending conversion utility you >> might loose that data. >> >> -- >> cyg Simple >> >> -- >> 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 >> > > -- > 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 > > -- 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
