Launch Service API Question

Hello, this is Qeye form China and i really need your help!

I am developing a macOS application which uses Launch Service API, specifically LSSetDefaultRoleHandlerForContentType and LSCopyDefaultRoleHandlerForContentType, but i had run into a problem that i couldn’t understand. please take a look at the code below.


/************** here start the code ******************/


(lldb) expression (OSStatus)LSSetDefaultRoleHandlerForContentType((CFStringRef)@"com.qeye.myplugin", 0xFFFFFFFF, (CFStringRef)@"com.qeye.CaseSensitive")
(OSStatus) $6 = 0
(lldb) expression (CFStringRef)LSCopyDefaultRoleHandlerForContentType((CFStringRef)(@"com.qeye.myplugin"), 0xFFFFFFFF)
(CFStringRef) $7 = 0x000060000045acd0 "com.qeye.casesensitive"


/************** code ends here ******************/

My question is why i set a case-sensitive bundle identifier, the result of LSCopyDefaultRoleHandlerForContentType is a case-insensitive instead?
Any help would be appreciated!