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Arm Compiler armclang Reference Guide : Localization library

Localization library

Describes implementation-defined aspects of the Arm® C++ compiler and C++ library relating to the localization library, as required by the ISO C++ Standard.

Locale object (
There is one global locale object for the entire program.
Permitted locale names (
Valid locale values depend on which __use_X_ctype symbols are imported (__use_iso8859_ctype, __use_sjis_ctype, __use_utf8_ctypte), and on user-defined locales.
Effect on C locale of calling locale::global (
Calling this function with an unnamed locale has no effect.
Value of ctype<char>::table_size (
The value of ctype<char>::table_size is 256.
Two-digit year numbers in the function std::time_get::do_get_year (
Two-digit year numbers are accepted. Years from 00 to 68 are assumed to mean years 2000 to 2068, while years from 69 to 99 are assumed to mean 1969 to 1999.
Additional formats for std::time_get::do_get_date (
No additional formats are defined.
Formatted character sequence that std::time_put::do_put generates in the C locale (
The behavior is the same as that of the Arm C library function strftime.
Mapping from name to catalog when calling std::messages::do_open (
No mapping happens as this function does not open any catalog.
Mapping to message when calling std::messages::do_get (
No mapping happens and dflt is always returned.