symlinks deleted on upgrade, but not during reinstall

[John H]

----- Original Message -----
> From: Jeff Johnson <n3npq at mac.com>
> To: John H <uothrawn at yahoo.com>
> Cc: 
> Sent: Tuesday, September 27, 2011 11:31 AM
> Subject: Re: symlinks deleted on upgrade, but not during reinstall

> Good, you've diagnosed most of what is happening already.
> 
> Try strace -f (to follow into all the helpers) and look for unlink calls from
> /sbin/ldconfig removing the symlink(s).
> 
> Expect a huge amount of spewage from strace. You can try adding "-e 
> unlink", but
> then you will lose the other context thyat is often useful from starching 
> through
> a hugely complex operation involving multiple processes.


Heres what it looks like is happening: the install of my openldap-2.4 is creating this symlink properly:

/usr/lib/libldap-2.3.so.0 -> libldap-2.4.so.2

In the %post install of my openldap-2.4, ldconfig is reassigning this symlink to point to "libldap-2.3.so.2.31".  Then, in the uninstall of openldap-2.3, libldap-2.3.so.2.31 is removed, but in its %post section ldconfig is removing my symlink (/usr/lib/libldap-2.3.so.0) because it no longer has a valid target.

How can I get ldconfig to not mess with my files ?

> What's likely happening is that running /sbin/ldconfig is removing the 
> symlinks.
> 
> And the like (just guessing) reason is that the soname within the library 
> executable
> disagrees with the symlinks you are attempting to package.
> 
> Use readelf -a to display the internal SONAME.


readelf -a gives an SONAME of libldap-2.4.so.2 for my libldap-2.3.so.0 symlink (as expected, given its a symlink). For the openldap-2.3.43 package, the SONAME is libldap-2.3.so.0.  As one would expect... Is this a concern? LDAP-based login functionality works if I have a symlink even though the SONAME is wrong.


Thanks.





> 
> 
> On Sep 27, 2011, at 10:34 AM, John H wrote:
> 
>>  I'm using CentOS 5.6 32bit with the stock OpenLDAP 2.3.43 and 
>> attempting to build an RPM for OpenLDAP 2.4.23.  A lot of things in CentOS 5.6 
>> depend on libldap-2.3.so.0 (among other 2.3 libs), so in my 2.4 specfile, I am 
>> creating a symlink in my %install section: 
>> 
>>  ln -s libldap-2.4.so.3 $RPM_BUILD_ROOT/usr/lib/libldap-2.3.so.0
>> 
>> 
>>  And adding a Provides tag of "libldap-2.3.so.0".
>> 
>>  However, whenever I upgrade the package (rpm -Uvh), the symlink isn't 
>> installed. I can then reinstall it, and have the symlink be available. My %files 
>> section has these definitions, so the symlink is definitely getting into the 
>> RPM: