ITP dos2unix 5.2.1-1

[Christian Franke]

Christopher Faylor wrote:
> On Wed, Mar 16, 2011 at 04:05:17PM -0400, Charles Wilson wrote:
>    
>> On 3/16/2011 3:32 PM, Christopher Faylor wrote:
>>      
>>> On Wed, Mar 16, 2011 at 08:29:51PM +0100, Christian Franke wrote:
>>>        
>>>> An alternative would be to modify cygutils+dos2unix packages such that
>>>> the user can select the flavor of dos2unix/unix2dos commands with
>>>> /usr/sbin/alternatives. If cygutils is the default if installed this
>>>> should not break anything.
>>>>          
>> Except you would no longer be able to run dos2unix/unix2dos/d2u/u2d from
>> a non-cygwin context, such as 'naked' cmd.exe or some IDE like Eclipse.
>>
>>      
>>> Hey, good idea, assuming that Chuck is amenable.  I'd be happy to just
>>> let the package in given that proviso if so.
>>>        
>> Uh, let's think about that a minute.
>>
>> cygutils is pulled in as part of Base (cygutils is not in the Base
>> category, but it is required by a packages that is: cygwin-doc).  Adding
>> alternatives as a dep of cygutils would then make alternatives an
>> implicit part of Base.  alternatives itself brings in no other unsavory
>> dependencies.
>>
>> This would be a change, since although alternatives is used by some very
>> common packages [vim, automake], it's not in the default Base-"only"
>> (actually, Base+requirements) installation.
>>
>> It also means that cygwin's dos2unix could no longer be executed from a
>> non-cygwin context, because of the symlinks.
>> ...
>>      
> Ah, right.
>
> I didn't get that Eric was referring to this scenario but, regardless,
> I should have remembered that alternatives means using symlinks.  Given
> the use that d2u is put, I don't think we want to make it a symlink.
>
>    

Agree, symlinks should be avoided.

Another alternative: Keep hard links as is if cygutils is installed 
only. If dos2unix is also installed assume that user opted-in to replace 
the dos2unix and unix2dos commands (and only these) with the linux 
variant. Undo this change if dos2unix is uninstalled.

This may be possible to handle this in the postinstall/preremove scripts 
of both packages as follows (dos2unix case only, not tested):

cygutils*.tar: remove dosunix2.exe but keep d2u.exe.

dosunix*.tar: Install dos2unix.exe as e.g. dos2unix-linux.exe

# /etc/postinstall/cygutils.sh:
if cmp -s /usr/bin/dos2unix-linux.exe /usr/bin/dos2unix.exe; then :; else
   ln -f /usr/bin/conv.exe /usr/bin/dos2unix.exe
fi

# /etc/preremove/cygutils.sh:
if cmp -s /usr/bin/conv.exe /usr/bin/dos2unix.exe; then
   rm -f /usr/bin/dos2unix.exe
fi

# /etc/postinstall/dos2unix.sh:
ln -f /usr/bin/dos2unix-linux.exe /usr/bin/dos2unix.exe

# /etc/preremove/dos2unix.sh:
if cmp -s /usr/bin/dos2unix-linux.exe /usr/bin/dos2unix.exe; then
   if test -f /usr/bin/conv.exe; then
     ln -f /usr/bin/conv.exe /usr/bin/dos2unix.exe
   else
     rm -f /usr/bin/dos2unix.exe
   fi
fi


Christian