It appears that `LC_COLLATE` controls the "alphabetical order" used by ls, as well. The US locale will sort as follows:

 a.C
 aFilename.C
 aFilename.H
 a.H

basically ignoring the periods. You might prefer:

 a.C
 a.H
 aFilename.C
 aFilename.H

I certainly do. Setting `LC_COLLATE` to `C` accomplishes this. Note that it will also sort lower case after all capitals:

 A.C
 A.H
 AFilename.C
 a.C
 a.H