Re: Fw: side-effect implementing the mv command

[Eric Blake]

Hi Derick,

According to Derick Centeno on 3/4/2010 3:38 AM:
> 
>> [please keep replies on the list, so that others may chime in]

Thanks for adding the list back in.

>> I asked for 'ls -l' so we could see full details, such as which files are
>> symlinks.  According to your screenshot, you happen to have plain 'ls'
>> aliased to a coloring version; with the four files on that line colored
>> red, black, green, and blue (I'm guessing dangling symlink, regular file,
>> symlink, executable); but rather than having to decode your colors, an 'ls
>> -l' would have shown that unambiguously in black and white.
>>
>>>
> 
> Thanks for the explanation regarding the function of ls -l, quite instructive.
> Note:  All directories are on the same disk.
> Here is your request:
> 
> address@hidden ~]$ cd /opt/ibm/java*/jre/plugin/ppc/ns7
> address@hidden ns7]$ ls -l
> total 164
> -rwxr-xr-x 1 root root 163244 Dec 14 23:39 libjavaplugin_oji.so
> address@hidden ns7]$ cd /usr/lib/mozilla/plugins
> address@hidden plugins]$ ls -l
> total 52
> lrwxrwxrwx 1 root   root      20 Dec 15 16:59 libgnashplugin.la
> -> ../libgnashplugin.la -rw-r--r-- 1 root   root     869 Jan 24  2008
> libgnashplugin.lai -rwxr-xr-x 1 root   root   45000 Jan 24  2008
> libgnashplugin.so lrwxrwxrwx 1 aguila aguila    60 Jan 13 22:39
> libjavaplugin_oji.so
> -> /opt/ibm/java-ppc-60/jre/plugin/ppc/ns7/libjavaplugin_oji.so 
> address@hidden plugins]$ 
> 
> As you can see libjavaplugin_oji.so in the ns7 directory is a shared object 
> not
> a symlink. What I reported earlier is accurate.  I originally executed mv in a
> non-standard manner on this shared object file itself.
> For me, developing an understanding mv's program logic as it executed a 
> symbolic
> link back to the shared object file would be worth pursuing.  

I'm still not sure I understand the exact settings you had before you ran
your mv command.  A transcript of the session that has the events that you
are questioning would go a long way to understand what you are even asking
about.

> 
> By the term, side effect, I mean unexpected/undocumented/ambiguous results
> generated by malformed or unusual commands.  The command I executed to mv
> was non-standard and produced the creation of a symbolic link which I've not
> found referrenced as a standard function of mv.  I believe deducing the 
> program
> logic executed by mv as it followed the directive as I structured it, is worth
> investigating.

mv creates a symlink in the destination directory if the source was a
symlink.  That's standard behavior.  I'm still not sure why you think
there is a side effect; mv does not create any symlinks except when moving
a symlink across devices.  Without something that we can do to reproduce
your actions, it's hard to tell you reasons for what you are seeing.  And
without a more detailed explanation of what you typed, what you expected,
and why what happened is different from what you expected, we can't tell
whether it was your expectations or the tool that had the problem.

-- 
Eric Blake   address@hidden    +1-801-349-2682
Libvirt virtualization library http://libvirt.org

signature.asc
Description: OpenPGP digital signature