os.readlink returning value

Giampaolo Rodola' gnewsg at gmail.com
Fri Nov 2 17:44:37 CET 2007


On 2 Nov, 05:30, "Gabriel Genellina" <gagsl-... at yahoo.com.ar> wrote:
> En Thu, 01 Nov 2007 22:51:14 -0300, Giampaolo Rodola' <gne... at gmail.com>  
> escribió:
>
> > I was reading os.readlink doc which says:
>
> > readlink( path)
>
> > Return a string representing the path to which the symbolic link
> > points. The result may be either an absolute or relative pathname; if
> > it is relative, it may be converted to an absolute pathname using
> > os.path.join(os.path.dirname(path), result). Availability: Macintosh,
> > Unix.
>
> > ...It's not clear to me when the returning result could be absolute
> > and when it could be relative.
> > Could someone clarify this point?
>
> That depends on how the symlink was created. Assume the current directory  
> is /usr/home/giampaolo/any/dir> ln -s ../foo/bar
>
> creates a symbolic link at /usr/home/giampaolo/any/dir/bar pointing to  
> ../foo/bar (relative to where the link resides). That is, actually  
> pointing to /usr/home/giampaolo/any/foo/bar (but this absolute path is NOT  
> stored on the link itself - only ../foo/bar)
>
> Now, a program whose current directory is /usr/home/giampaolo executes  
> this:
> readlink("any/dir/bar")
> It will return the string "../foo/bar". One must resolve the .. reference  
> relative to where the link resides, NOT relative to the current directory.  
> That is, relative to any/dir. os.path.dirname("any/dir/bar") returns  
> exactly that. Then, the suggested expression in the docs evaluates to  
> "any/dir/../foo/bar" - it's not an absolute pathname yet, one should use  
> abspath() on it. Or instead  
> os.path.join(os.path.abspath(os.path.dirname(path)), result)
>
> --
> Gabriel Genellina

Thanks for the examplanation.
I'd only want to do the same as what ls does in such cases.
Imho, os.readlink() should have the same behaviour of ls, isn't it?




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