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Andre Schnoor

Symbolic Links

Does a solution exist for OSX / Unixes? I mean, something like this

Filename>>isSymbolicLink
Filename>>createSymbolicLinkTo: aTargetFilename
Filename>>symbolicLinkTarget

Programatically creating a directory tree with (relative) symbolic links
seems to be a really difficult task. I have no idea how to do that
efficiently. Invoking external shell commands wouldn't be my first choice.

Andre

Andre Schnoor

Re: Symbolic Links

Thanks Nick, that seems to be a nice approach. Although implementing the stat() and lstat() calls with their structs might be a little more work.

I am currently using the Cocoa interface on OSX as a workaround, which also works fine. This solution however, will not run on other Unixes (see below). A clean stat() and lstat() implementation would probably be better.

Andre

    MacOSXFilename>>createSymbolicLink: targetFilename
        ^NSFileManager defaultManager
          createSymbolicLinkAtPath: self
            pathContent: targetFilename

    MacOSXFilename>>isSymbolicLink
      ^(NSFileManager defaultManager
          pathContentOfSymbolicLinkAtPath: self asString) notNil

    MacOSXFilename>>symbolicLinkTarget
      | str |
        str := NSFileManager defaultManager
            pathContentOfSymbolicLinkAtPath: self asString.
        ^str isNil
          ifTrue:[ nil ]
            ifFalse:[ str asFilename ]

Nick Yannakoyorgos wrote:

Andre,

Try the attached which simply implements the symlink() Unix call. Use as:

(Filename named: '/tmp/sourcefile') linkTo: (Filename named: '/tmp/targetlink')

A very quick look through the engine code didn't show an implementation of symlink().

Nick

Andre Schnoor wrote:

Does a solution exist for OSX / Unixes? I mean, something like this

   Filename>>isSymbolicLink
   Filename>>createSymbolicLinkTo: aTargetFilename
   Filename>>symbolicLinkTarget

Programatically creating a directory tree with (relative) symbolic links seems to be a really difficult task. I have no idea how to do that efficiently. Invoking external shell commands wouldn't be my first choice.

Andre
<?xml version="1.0"?>

<st-source>
<time-stamp>From VisualWorksÂ®, 7.4 of December 5, 2005 on June 17, 2007 at 10:40:17 am</time-stamp>


<methods>
<class-id>OS.UnixSystemSupport</class-id> <category>procedures</category>

<body package="Standard IO Streams" selector="symlink:to:">symlink: oldpath to: newpath

	&lt;C: int symlink(char * oldpath, char * newpath)&gt;
	^self externalAccessFailedWith: _errorCode</body>
</methods>
<methods>
<class-id>OS.Filename</class-id> <category>file utilities</category>

<body package="OS-Support" selector="linkTo:">linkTo: anotherFilename

	OSSystemSupport concreteClass new 
		symlink: (self class encodeFilename: self asString)
		to: (self class encodeFilename: anotherFilename asString)</body>
</methods>

</st-source>
  

-- 
Andre Schnoor
Cognitone GmbH
www.cognitone.com

Dave Stevenson-2

Re: Symbolic Links

I don't know how applicable it would be to non-linux plats, but in case
it is helpful at least as a starting point I thought I'd mention that
some years ago Pete wrote some code for the packaging tool to use, which
is found here:
$VISUALWORKS/contributed/LinuxSymlinkSupport.pcl
and the client code is here:
$VISUALWORKS/contributed/PackingListTool.pcl

I believe he may have more general code somewhere that he plans to
integrate at some point, but I could be wrong.

Dave

Andre Schnoor wrote:

> Thanks Nick, that seems to be a nice approach. Although implementing the
> stat() and lstat() calls with their structs might be a little more work.
>
> I am currently using the Cocoa interface on OSX as a workaround, which
> also works fine. This solution however, will not run on other Unixes
> (see below). A clean stat() and lstat() implementation would probably be
> better.
>
> Andre
>
>
>
> MacOSXFilename>>createSymbolicLink: targetFilename
> ^NSFileManager defaultManager
> createSymbolicLinkAtPath: self
> pathContent: targetFilename
>
> MacOSXFilename>>isSymbolicLink
> ^(NSFileManager defaultManager
> pathContentOfSymbolicLinkAtPath: self asString) notNil
>
> MacOSXFilename>>symbolicLinkTarget
> | str |
> str := NSFileManager defaultManager
> pathContentOfSymbolicLinkAtPath: self asString.
> ^str isNil
> ifTrue:[ nil ]
> ifFalse:[ str asFilename ]
>
>
>
>
> Nick Yannakoyorgos wrote:
>> Andre,
>>
>> Try the attached which simply implements the symlink() Unix call. Use as:
>>
>> (Filename named: '/tmp/sourcefile') linkTo: (Filename named:
>> '/tmp/targetlink')
>>
>> A very quick look through the engine code didn't show an
>> implementation of symlink().
>>
>> Nick
>>
>> Andre Schnoor wrote:
>>> Does a solution exist for OSX / Unixes? I mean, something like this
>>>
>>> Filename>>isSymbolicLink
>>> Filename>>createSymbolicLinkTo: aTargetFilename
>>> Filename>>symbolicLinkTarget
>>>
>>> Programatically creating a directory tree with (relative) symbolic
>>> links seems to be a really difficult task. I have no idea how to do
>>> that efficiently. Invoking external shell commands wouldn't be my
>>> first choice.
>>>
>>> Andre
>>>
>>
>> ------------------------------------------------------------------------
>>
>> <?xml version="1.0"?>
>>
>> <st-source>
>> <time-stamp>From VisualWorksÂ®, 7.4 of December 5, 2005 on June 17, 2007 at 10:40:17 am</time-stamp>
>>
>>
>> <methods>
>> <class-id>OS.UnixSystemSupport</class-id> <category>procedures</category>
>>
>> <body package="Standard IO Streams" selector="symlink:to:">symlink: oldpath to: newpath
>>
>> <C: int symlink(char * oldpath, char * newpath)>
>> ^self externalAccessFailedWith: _errorCode</body>
>> </methods>
>> <methods>
>> <class-id>OS.Filename</class-id> <category>file utilities</category>
>>
>> <body package="OS-Support" selector="linkTo:">linkTo: anotherFilename
>>
>> OSSystemSupport concreteClass new
>> symlink: (self class encodeFilename: self asString)
>> to: (self class encodeFilename: anotherFilename asString)</body>
>> </methods>
>>
>> </st-source>
>>
>
> --
> Andre Schnoor
> Cognitone GmbH
> www.cognitone.com
>