Re: [Mingw-users] grep -f is MSDOS incapable

[Keith M. <kei...@us...>]

On Wednesday 31 March 2010 23:22:41 Charles Wilson wrote:
> On 3/31/2010 5:19 PM, Keith Marshall wrote:
> > There is one tool, which is guaranteed to be both ubiquitous and
> > consistently portable, for converting between MS-Windows CRLF
> > and Unix LF line endings -- the venerable `awk'; this is
> > precisely what the `d2u' and 'u2d' filters in recent MSYS base
> > use to achieve the conversion.
>
> Um, Keith -- stop saying that.
>
> The script-based filters are no longer provided in "recent" MSYS.
> AFAICT, they were removed in 1.0.12.  Instead, the
> cygutils-dos2unix-msys and cygutils-dos2unix-mingw32 packages
> provide all of the desired functionality, in both msys-aware and
> "normal" win32 modes.  Even filtering.

Sorry; perhaps I didn't fully appreciate the significance of...

> Search your mail archives for an (offlist) message titled:
> "lpr and cygutils" back in August, 2009. Also, see:
>
> http://article.gmane.org/gmane.comp.gnu.mingw.devel/3452
> Updated packages available (wave 6)
>
> > MSYS cygutils also provides implementations of dos2unix and
> > unix2dos (u2d, d2u) that supplant the u2d and d2u shell scripts
> > installed by msysCORE, as well as the dos2unix and unix2dos
> > executables provided by mingw-utils-0.3.  These new versions
> > are, obviously, MSYS-dependent.

I had thought that the basic scripts were to be supplanted only for 
those users who CHOSE to install the cygutils add-on package, and 
that those users who didn't adopt this choice would still have the 
capability to filter MS-DOS style line endings using the scripts.  
Personally, I can't see what benefit might accrue from the extra 
bloat of a (somewhat non-portable) .exe, when a ubiquitous filter 
program achieves the desired effect, in a more universally portable 
manner; the effect of dos2unix is as simple[1] as:

  $ awk '{sub("\r$",""); print}' dosfile > unixfile

(or the completely equivalent):

  $ awk '{sub("\r$",""); printf "%s\n", $0}' dosfile > unixfile

while unix2dos yields the equivalent of:

  $ awk '{sub("\r$",""); printf "%s\r\n", $0}' unixfile > dosfile

and IMO, the not-so-standardised options provided by dos2unix and 
unix2dos, (in the absence of standardisation), are little more than 
window dressing.

[1] Of course, this simple implementation depends on having an awk 
which doesn't have CRLF line endings mangled behind its back by the 
platform runtime library's I/O subsystem, (a typically Microsoft 
(mis)feature which, thankfully, MSYS' awk does not exhibit).

-- 
Regards,
Keith.