Re: bracket expressions and POSIX

[Clint Adams <clint@zsh.org>]

> IIRC POSIX does not deal with locale so it is a bit offtopic w.r.t. POSIX
> compatibility. But XPG/SUS do. Anybody with access to pure POSIX (even
> drafts would do; I have access only to XPG).

The standard utilities in the Shell and Utilities volume of IEEE Std 1003.1-200x shall base their
behavior on the current locale, as defined in the ENVIRONMENT VARIABLES section for each
utility. The behavior of some of the C-language functions defined in the System Interfaces
volume of IEEE Std 1003.1-200x shall also be modified based on the current locale, as defined by
the last call to setlocale ().

Locales other than those supplied by the implementation can be created via the localedef utility,
provided that the _POSIX2_LOCALEDEF symbol is defined on the system. Even if localedef is not
provided, all implementations conforming to the System Interfaces volume of
IEEE Std 1003.1-200x shall provide one or more locales that behave as described in this chapter.
The input to the utility is described in Section 7.3 (on page 122). The value that is used to specify
a locale when using environment variables shall be the string specified as the name operand to
the localedef utility when the locale was created. The strings "C" and "POSIX" are reserved as
identifiers for the POSIX locale (see Section 7.2 (on page 122)). When the value of a locale
environment variable begins with a slash ( / ), it shall be interpreted as the pathname of the
locale definition; the type of file (regular, directory, and so on) used to store the locale definition
is implementation-defined. If the value does not begin with a slash, the mechanism used to
locate the locale is implementation-defined.