function IdGetDefaultCharSet: TIdCharSet;

TIdCharSet - Character set for the platform or operating system.

IdGetDefaultCharSet is a TIdCharSet function used to get the default character set for the platform or operating system hosting the Indy library. 

For the Windows platform, the primary language for the system locale is used to determine the return value for the method using the following: 

For the .Net platform, the return value is the generic idcsUNICODE_1_1 encoding. 

For the Linux platform, the value in the GIdDefaultCharSet global variable is used as the return value for the function.