[Phpwm] ltrin inconsistency

[Phil Beynon]

Has anyone seen or know the answer to this apparent inconsistency with the
ltrim() command;
I'm storing some image names in a database, these have prepended to them a
directory path which when displaying just the filename needs to be dropped.
So what I did was this;

ltrim($myrow["thumb_name"],"./75px/");
ltrim($myrow["large_name"],"./150px/");
ltrim($myrow["big_name"],"./250px/");

which as far as I can should work, generally it does - but for some reason
its not consistent but appears to stabily inconsistent;

These ones work just fine;

full = ./75px/tn_e2cc_3.jpg trimmed = tn_e2cc_3.jpg
full = ./150px/e2cc_3.jpg trimmed = e2cc_3.jpg
full = ./250px/e2cc_3.jpg trimmed = e2cc_3.jpg

full = ./75px/tn_6e57_chick.jpg trimmed = tn_6e57_chick.jpg
full = ./150px/6e57_chick.jpg trimmed = 6e57_chick.jpg
full = ./250px/6e57_chick.jpg trimmed = 6e57_chick.jpg

full = ./75px/tn_8139_phil3.JPG trimmed = tn_8139_phil3.JPG
full = ./150px/8139_phil3.JPG trimmed = 8139_phil3.JPG
full = ./250px/8139_phil3.JPG trimmed = 8139_phil3.JPG

full = ./75px/tn_ada8_james.JPG trimmed = tn_ada8_james.JPG
full = ./150px/ada8_james.JPG trimmed = ada8_james.JPG
full = ./250px/ada8_james.JPG trimmed = ada8_james.JPG

This one always loses either the "51" or "5" as if it was running further
into the file name.

full = ./75px/tn_51eb_expensivepiss.jpg trimmed = tn_51eb_expensivepiss.jpg
full = ./150px/51eb_expensivepiss.jpg trimmed = eb_expensivepiss.jpg
full = ./250px/51eb_expensivepiss.jpg trimmed = 1eb_expensivepiss.jpg

Sorry about the name on that one, it was a humorous picture of a puppy and a
laptop! :-)

It doesn't seem to be obvious why it should be doing this that I can see -
it doesnt seem to have any bearing on string length or anything really
visibly different with the prepended directory name, which is always the
same.

I've altered the code to;
substr_replace($myrow["big_name"],"",0,8);
which seems to work fine in all cases, but I'd still like to get my head
around why the other method failed some of the time.


Regards,

Phil