Using join with two files fails on larger file sizes

Question

I am having some issues with a script that is using join to join two files. Eaxmple input files contains lines like this:

Here are the input file and the output of the join command:

D:\work\BuildScripts\3C>cat D:\temp\aaa.txt
hzapplications\adn\adn4\adn4density\adn4_idd_module.cpp,83
hzapplications\adn\adn4\adn4density\adn4dencalmodule.cpp,73
hzapplications\adn\adn4\adn4density\adn4denimagemodulerm.cpp,111
hzapplications\adn\adn4\adn4density\adn4denimagemodulert.cpp,202
hzapplications\adn\adn4\adn4density\adn4densityanqmodules.cpp,445
hzapplications\adn\adn4\adn4density\adn4densityappl.cpp,378
hzapplications\adn\adn4\adn4density\adn4densityappl.h,50
hzapplications\adn\adn4\adn4density\adn4densityevrmodules.cpp,272
hzapplications\adn\adn4\adn4density\adn4densitykernel.cpp,490
hzapplications\adn\adn4\adn4density\adn4densitykernel.h,65
hzapplications\adn\adn4\adn4density\adn4densitysecimgmodule.cpp,209
hzapplications\adn\adn4\adn4density\adn4densitysecimgmodule.h,70
hzapplications\adn\adn4\adn4density\adn4densitysecmodule.cpp,218
hzapplications\adn\adn4\adn4density\adn4densitysecmodule.h,70
hzapplications\adn\adn4\adn4density\adn4dphimodules.cpp,610
hzapplications\adn\adn4\adn4density\adn4dphimodulesrt.cpp,115
hzapplications\adn\adn4\adn4density\adn4rhomodulesrt.cpp,102

D:\work\BuildScripts\3C>cat D:\temp\bbb.txt
hzapplications\activect\ptc\ictsx01\ictsx01_bootuptask.cpp,1
hzapplications\activeps\iola\acquisition\iola_acqmodule.cpp,4
hzapplications\activeps\iola\simulation\iola_simmodule.cpp,3
hzapplications\activeps\iolr\simulation\iolr_simmodule.cpp,1
hzapplications\activeps\iolr\task\iolr_poweron200vhitask.cpp,1
hzapplications\activeps\iolr\task\iolr_poweron200vlowtask.cpp,1
hzapplications\activeps\iolr\task\iolr_poweronnrlvtask.cpp,1
hzapplications\activeps\iolr\task\iolrtaskcommon.cpp,2
hzapplications\adn\adn4\adn4density\adn4densitykernel.cpp,1
hzapplications\adn\adn4\adn4equipment\adn4adseelem.cpp,1
hzapplications\adn\adn4\adn4equipment\adn4collar.cpp,1
hzapplications\adn\adn4\adn4equipment\adn4tool.cpp,2
hzapplications\adn\adn6c\adn6cequipment\adn6ccollar.cpp,1
hzapplications\adn\adn8\adn8equipment\adn8tool.cpp,1
hzapplications\adn\adn8\adn8neutron\adn8neutronkernel.cpp,1
hzapplications\adn\adn8d\adn8ddensity\adn8ddensitykernel.cpp,1
hzapplications\adn\adn8d\adn8dequipment\adn8dtool.cpp,1

D:\work\BuildScripts\3C>join --ignore-case -1 1 -2 1 -t"," -o "1.1,1.2,2.2" -e "0" -a 1 D:\temp\aaa.txt D:\temp\bbb.txt
hzapplications\adn\adn4\adn4density\adn4_idd_module.cpp,83,0
hzapplications\adn\adn4\adn4density\adn4dencalmodule.cpp,73,0
hzapplications\adn\adn4\adn4density\adn4denimagemodulerm.cpp,111,0
hzapplications\adn\adn4\adn4density\adn4denimagemodulert.cpp,202,0
hzapplications\adn\adn4\adn4density\adn4densityanqmodules.cpp,445,0
hzapplications\adn\adn4\adn4density\adn4densityappl.cpp,378,0
hzapplications\adn\adn4\adn4density\adn4densityappl.h,50,0
hzapplications\adn\adn4\adn4density\adn4densityevrmodules.cpp,272,0
hzapplications\adn\adn4\adn4density\adn4densitykernel.cpp,490,0
hzapplications\adn\adn4\adn4density\adn4densitykernel.h,65,0
hzapplications\adn\adn4\adn4density\adn4densitysecimgmodule.cpp,209,0
hzapplications\adn\adn4\adn4density\adn4densitysecimgmodule.h,70,0
hzapplications\adn\adn4\adn4density\adn4densitysecmodule.cpp,218,0
hzapplications\adn\adn4\adn4density\adn4densitysecmodule.h,70,0
hzapplications\adn\adn4\adn4density\adn4dphimodules.cpp,610,0
hzapplications\adn\adn4\adn4density\adn4dphimodulesrt.cpp,115,0
hzapplications\adn\adn4\adn4density\adn4rhomodulesrt.cpp,102,0

D:\work\BuildScripts\3C>

The expected output is that this particular line is joined like so: hzapplications\adn\adn4\adn4density\adn4densitykernel.cpp,490,1

Any suggests are most welcome. I am using the unxutils package on windows, this is the exact version:

D:\work\BuildScripts\3C>join --version
join (GNU textutils) 2.0
Written by Mike Haertel.

Copyright (C) 1999 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

Answer 1

It turns out that --ignore-case is the problem. It has an effect even when there are no uppercase letters because it treats all lowercase letters as uppercase, causing them to jump to the other side of the characters that are between the uppercase and lowercase in ASCII order: [\]^_

In normal sorted order, iolrt comes after iolr_ but in --ignore-case order they are reversed.

The sort command needs the -f option to produce the correct order. (In addition to -t, and -k1,1)