photos.search result not "stable" - paging not usable

[alexs77]

I did a search for my pictures having a certain tag using the flickcurl CLI tool. I noticed, that when I do the exact same search again, the results are different. Because of this, paging cannot be used in a useful way.

Example:

$ flickcurl photos.search per-page 3 page 2 user me tags cassandra
$ flickcurl photos.search per-page 3 page 2 user me tags cassandra > /tmp/search.1
$ flickcurl photos.search per-page 3 page 2 user me tags cassandra > /tmp/search.2
$ cmp /tmp/search.? 
/tmp/search.1 /tmp/search.2 differ: byte 136, line 3

Search outputs:

• search.1
• search.2
• NB: The images returned in the searches have now been set to be non-public.

Now, if the two searches would have returned the same output, the cmp should't have returned anything (because the output would've been identical). And when I manually compare the files /tmp/search.1 and /tmp/search.2 (ie. the output of both photos.search invocations), I see that indeed other pictures have been returned.

$ diff -U0 /tmp/search.{1,2}
--- /tmp/search.1	2017-02-13 10:10:45.702682787 +0100
+++ /tmp/search.2	2017-02-13 10:10:47.677719128 +0100
@@ -3 +3 @@
-photo with URI (Unknown) ID 30908489162 and 0 tags
+photo with URI (Unknown) ID 31050737945 and 0 tags
…

10:16% flickcurl -V  
Flickr API utility 1.25
Flickcurl home page: http://librdf.org/flickcurl/
Copyright (C) 2007-2013 David Beckett - http://www.dajobe.org/
License: LGPL 2.1 or newer, GPL 2 or newer, Apache 2.0 or newer.
See http://librdf.org/flickcurl/ for full terms.

Try `flickcurl --help' for more information.
(1)10:16% lsb_release -a
No LSB modules are available.
Distributor ID:	Ubuntu
Description:	Ubuntu 16.04.2 LTS
Release:	16.04
Codename:	xenial