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Section: 30.4.8.2 [locale.messages] Status: C++14 Submitter: Howard Hinnant Opened: 2011-02-14 Last modified: 2016-01-28
Priority: Not Prioritized
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Discussion:
In 30.4.8.2 [locale.messages], messages_base::catalog is specified to be a typedef to int. This type is subsequently used to open, access and close catalogs.
However, an OS may have catalog/messaging services that are indexed and managed by types other than int. For example POSIX, publishes the following messaging API:
typedef unspecified nl_catd; nl_catd catopen(const char* name , int oflag); char* catgets(nl_catd catd, int set_id, int msg_id, const char* s); int catclose(nl_catd catd);
I.e., the catalog is managed with an unspecified type, not necessarily an int. Mac OS uses a void* for nl_catd (which is conforming to the POSIX standard). The current messages_base spec effectively outlaws using the built-in OS messaging service supplied for this very purpose!
[2011-02-24: Chris Jefferson updates the proposed wording, changing unspecified to unspecified signed integral type]
[2011-03-02: Daniel updates the proposed wording, changing unspecified signed integral type to unspecified signed integer type (We don't want to allow for bool or char)]
[2011-03-24 Madrid meeting]
Consensus that this resolution is the direction we would like to see.
Proposed resolution:
Modify 30.4.8.2 [locale.messages]:
namespace std {
class messages_base {
public:
typedef intunspecified signed integer type catalog;
};
...
}