=back
-C<LC_COLLATE>, C<LC_CTYPE>, and so on, are discussed further in L<LOCALE
-CATEGORIES>.
+C<LC_COLLATE>, C<LC_CTYPE>, and so on, are discussed further in
+L<LOCALE CATEGORIES>.
The default behavior is restored with the S<C<no locale>> pragma, or
upon reaching the end of block enclosing C<use locale>.
ls /usr/lib/nls
+ ls /usr/share/locale
+
and see whether they list something resembling these
en_US.ISO8859-1 de_DE.ISO8859-1 ru_RU.ISO8859-5
english.iso88591 german.iso88591 russian.iso88595
english.roman8 russian.koi8r
-Sadly, even though the calling interface for setlocale() has
-been standardized, names of locales and the directories where the
+Sadly, even though the calling interface for setlocale() has been
+standardized, names of locales and the directories where the
configuration resides have not been. The basic form of the name is
-I<language_country/territory>B<.>I<codeset>, but the latter parts after
-I<language> are not always present. The I<language> and I<country> are
-usually from the standards B<ISO 3166> and B<ISO 639>, the two-letter
-abbreviations for the countries and the languages of the world,
-respectively. The I<codeset> part often mentions some B<ISO 8859>
-character set, the Latin codesets. For example, C<ISO 8859-1> is the
-so-called "Western codeset" that can be used to encode most Western
-European languages. Again, there are several ways to write even the
-name of that one standard. Lamentably.
+I<language_territory>B<.>I<codeset>, but the latter parts after
+I<language> are not always present. The I<language> and I<country>
+are usually from the standards B<ISO 3166> and B<ISO 639>, the
+two-letter abbreviations for the countries and the languages of the
+world, respectively. The I<codeset> part often mentions some B<ISO
+8859> character set, the Latin codesets. For example, C<ISO 8859-1>
+is the so-called "Western European codeset" that can be used to encode
+most Western European languages adequately. Again, there are several
+ways to write even the name of that one standard. Lamentably.
Two special locales are worth particular mention: "C" and "POSIX".
Currently these are effectively the same locale: the difference is
locale inconsistencies or to run Perl under the default locale "C".
Perl's moaning about locale problems can be silenced by setting the
-environment variable PERL_BADLANG to a non-zero value, for example
-"1". This method really just sweeps the problem under the carpet: you
-tell Perl to shut up even when Perl sees that something is wrong. Do
-not be surprised if later something locale-dependent misbehaves.
+environment variable PERL_BADLANG to a zero value, for example "0".
+This method really just sweeps the problem under the carpet: you tell
+Perl to shut up even when Perl sees that something is wrong. Do not
+be surprised if later something locale-dependent misbehaves.
Perl can be run under the "C" locale by setting the environment
variable LC_ALL to "C". This method is perhaps a bit more civilized
other locale variables) may affect other programs as well, not just
Perl. In particular, external programs run from within Perl will see
these changes. If you make the new settings permanent (read on), all
-programs you run see the changes. See L<ENVIRONMENT> for for
+programs you run see the changes. See L<ENVIRONMENT> for
the full list of relevant environment variables and L<USING LOCALES>
for their effects in Perl. Effects in other programs are
easily deducible. For example, the variable LC_COLLATE may well affect
locale "En_US"--and in Cshish shells (B<csh>, B<tcsh>)
setenv LC_ALL en_US.ISO8859-1
-
+
If you do not know what shell you have, consult your local
helpdesk or the equivalent.
(prefix matches do not count and case usually counts) like "En_US"
without the quotes, then you should be okay because you are using a
locale name that should be installed and available in your system.
-In this case, see L<Fixing system locale configuration>.
+In this case, see L<Permanently fixing your system's locale configuration>.
-=head2 Permanently fixing your locale configuration
+=head2 Permanently fixing your system's locale configuration
This is when you see something like:
the same. In this case, try running under a locale
that you can list and which somehow matches what you tried. The
rules for matching locale names are a bit vague because
-standardization is weak in this area. See again the L<Finding
-locales> about general rules.
+standardization is weak in this area. See again the
+L<Finding locales> about general rules.
-=head2 Permanently fixing system locale configuration
+=head2 Fixing system locale configuration
Contact a system administrator (preferably your own) and report the exact
error message you get, and ask them to read this same documentation you
if you "use locale".
A B C D E a b c d e
- A a B b C c D d D e
+ A a B b C c D d E e
a A b B c C d D e E
a b c d e A B C D E
-Here is a code snippet to tell what alphanumeric
+Here is a code snippet to tell what "word"
characters are in the current locale, in that locale's order:
use locale;
- print +(sort grep /\w/, map { chr() } 0..255), "\n";
+ print +(sort grep /\w/, map { chr } 0..255), "\n";
Compare this with the characters that you see and their order if you
state explicitly that the locale should be ignored:
no locale;
- print +(sort grep /\w/, map { chr() } 0..255), "\n";
+ print +(sort grep /\w/, map { chr } 0..255), "\n";
This machine-native collation (which is what you get unless S<C<use
locale>> has appeared earlier in the same block) must be used for
In the scope of S<C<use locale>>, Perl obeys the C<LC_CTYPE> locale
setting. This controls the application's notion of which characters are
alphabetic. This affects Perl's C<\w> regular expression metanotation,
-which stands for alphanumeric characters--that is, alphabetic and
-numeric characters. (Consult L<perlre> for more information about
+which stands for alphanumeric characters--that is, alphabetic,
+numeric, and including other special characters such as the underscore or
+hyphen. (Consult L<perlre> for more information about
regular expressions.) Thanks to C<LC_CTYPE>, depending on your locale
setting, characters like 'E<aelig>', 'E<eth>', 'E<szlig>', and
'E<oslash>' may be understood as C<\w> characters.
These functions aren't aware of such niceties as thousands separation and
so on. (See L<The localeconv function> if you care about these things.)
-Output produced by print() is B<never> affected by the
-current locale: it is independent of whether C<use locale> or C<no
-locale> is in effect, and corresponds to what you'd get from printf()
-in the "C" locale. The same is true for Perl's internal conversions
-between numeric and string formats:
+Output produced by print() is also affected by the current locale: it
+depends on whether C<use locale> or C<no locale> is in effect, and
+corresponds to what you'd get from printf() in the "C" locale. The
+same is true for Perl's internal conversions between numeric and
+string formats:
use POSIX qw(strtod);
use locale;
$n = 5/2; # Assign numeric 2.5 to $n
- $a = " $n"; # Locale-independent conversion to string
+ $a = " $n"; # Locale-dependent conversion to string
- print "half five is $n\n"; # Locale-independent output
+ print "half five is $n\n"; # Locale-dependent output
printf "half five is %g\n", $n; # Locale-dependent output
that is affected by its contents. (Those with experience of standards
committees will recognize that the working group decided to punt on the
issue.) Consequently, Perl takes no notice of it. If you really want
-to use C<LC_MONETARY>, you can query its contents--see L<The localeconv
-function>--and use the information that it returns in your application's
-own formatting of currency amounts. However, you may well find that
-the information, voluminous and complex though it may be, still does not
-quite meet your requirements: currency formatting is a hard nut to crack.
+to use C<LC_MONETARY>, you can query its contents--see
+L<The localeconv function>--and use the information that it returns in your
+application's own formatting of currency amounts. However, you may well
+find that the information, voluminous and complex though it may be, still
+does not quite meet your requirements: currency formatting is a hard nut
+to crack.
=head2 LC_TIME
The remaining locale category, C<LC_MESSAGES> (possibly supplemented
by others in particular implementations) is not currently used by
-Perl--except possibly to affect the behavior of library functions called
-by extensions outside the standard Perl distribution.
+Perl--except possibly to affect the behavior of library functions
+called by extensions outside the standard Perl distribution and by the
+operating system and its utilities. Note especially that the string
+value of C<$!> and the error messages given by external utilities may
+be changed by C<LC_MESSAGES>. If you want to have portable error
+codes, use C<%!>. See L<Errno>.
=head1 SECURITY
=item *
-If the decimal point character in the C<LC_NUMERIC> locale is
-surreptitiously changed from a dot to a comma, C<sprintf("%g",
-0.123456e3)> produces a string result of "123,456". Many people would
-interpret this as one hundred and twenty-three thousand, four hundred
-and fifty-six.
-
-=item *
-
A sneaky C<LC_COLLATE> locale could result in the names of students with
"D" grades appearing ahead of those with "A"s.
=over 4
-=item B<Comparison operators> (C<lt>, C<le>, C<ge>, C<gt> and C<cmp>):
+=item *
+
+B<Comparison operators> (C<lt>, C<le>, C<ge>, C<gt> and C<cmp>):
Scalar true/false (or less/equal/greater) result is never tainted.
-=item B<Case-mapping interpolation> (with C<\l>, C<\L>, C<\u> or C<\U>)
+=item *
+
+B<Case-mapping interpolation> (with C<\l>, C<\L>, C<\u> or C<\U>)
Result string containing interpolated material is tainted if
C<use locale> is in effect.
-=item B<Matching operator> (C<m//>):
+=item *
+
+B<Matching operator> (C<m//>):
Scalar true/false result never tainted.
C<use locale> is in effect and the regular expression contains C<\w>,
C<\W>, C<\s>, or C<\S>.
-=item B<Substitution operator> (C<s///>):
+=item *
+
+B<Substitution operator> (C<s///>):
Has the same behavior as the match operator. Also, the left
operand of C<=~> becomes tainted when C<use locale> in effect
expression match involving C<\w>, C<\W>, C<\s>, or C<\S>; or of
case-mapping with C<\l>, C<\L>,C<\u> or C<\U>.
-=item B<In-memory formatting function> (sprintf()):
+=item *
-Result is tainted if C<use locale> is in effect.
+B<Output formatting functions> (printf() and write()):
-=item B<Output formatting functions> (printf() and write()):
+Results are never tainted because otherwise even output from print,
+for example C<print(1/7)>, should be tainted if C<use locale> is in
+effect.
-Success/failure result is never tainted.
+=item *
-=item B<Case-mapping functions> (lc(), lcfirst(), uc(), ucfirst()):
+B<Case-mapping functions> (lc(), lcfirst(), uc(), ucfirst()):
Results are tainted if C<use locale> is in effect.
-=item B<POSIX locale-dependent functions> (localeconv(), strcoll(),
+=item *
+
+B<POSIX locale-dependent functions> (localeconv(), strcoll(),
strftime(), strxfrm()):
Results are never tainted.
-=item B<POSIX character class tests> (isalnum(), isalpha(), isdigit(),
+=item *
+
+B<POSIX character class tests> (isalnum(), isalpha(), isdigit(),
isgraph(), islower(), isprint(), ispunct(), isspace(), isupper(),
isxdigit()):
A string that can suppress Perl's warning about failed locale settings
at startup. Failure can occur if the locale support in the operating
system is lacking (broken) in some way--or if you mistyped the name of
-a locale when you set up your environment. If this environment variable
-is absent, or has a value that does not evaluate to integer zero--that
-is, "0" or ""--Perl will complain about locale setting failures.
+a locale when you set up your environment. If this environment
+variable is absent, or has a value that does not evaluate to integer
+zero--that is, "0" or ""-- Perl will complain about locale setting
+failures.
B<NOTE>: PERL_BADLANG only gives you a way to hide the warning message.
The message tells about some problem in your system's locale support,
C<LC_ALL> is the "override-all" locale environment variable. If
set, it overrides all the rest of the locale environment variables.
+=item LANGUAGE
+
+B<NOTE>: C<LANGUAGE> is a GNU extension, it affects you only if you
+are using the GNU libc. This is the case if you are using e.g. Linux.
+If you are using "commercial" UNIXes you are most probably I<not>
+using GNU libc and you can ignore C<LANGUAGE>.
+
+However, in the case you are using C<LANGUAGE>: it affects the
+language of informational, warning, and error messages output by
+commands (in other words, it's like C<LC_MESSAGES>) but it has higher
+priority than L<LC_ALL>. Moreover, it's not a single value but
+instead a "path" (":"-separated list) of I<languages> (not locales).
+See the GNU C<gettext> library documentation for more information.
+
=item LC_CTYPE
In the absence of C<LC_ALL>, C<LC_CTYPE> chooses the character type
(see L<The setlocale function>). By default, Perl still behaves this
way for backward compatibility. If you want a Perl application to pay
attention to locale information, you B<must> use the S<C<use locale>>
-pragma (see L<The use locale Pragma>) to instruct it to do so.
+pragma (see L<The use locale pragma>) to instruct it to do so.
Versions of Perl from 5.002 to 5.003 did use the C<LC_CTYPE>
information if available; that is, C<\w> did understand what
is broken and cannot be fixed or used by Perl. Such deficiencies can
and will result in mysterious hangs and/or Perl core dumps when the
C<use locale> is in effect. When confronted with such a system,
-please report in excruciating detail to <F<perlbug@perl.com>>, and
+please report in excruciating detail to <F<perlbug@perl.org>>, and
complain to your vendor: bug fixes may exist for these problems
in your operating system. Sometimes such bug fixes are called an
operating system upgrade.
=head1 SEE ALSO
-L<POSIX (3)/isalnum>
-
-L<POSIX (3)/isalpha>
-
-L<POSIX (3)/isdigit>
-
-L<POSIX (3)/isgraph>
-
-L<POSIX (3)/islower>
-
-L<POSIX (3)/isprint>,
-
-L<POSIX (3)/ispunct>
-
-L<POSIX (3)/isspace>
-
-L<POSIX (3)/isupper>,
-
-L<POSIX (3)/isxdigit>
-
-L<POSIX (3)/localeconv>
-
-L<POSIX (3)/setlocale>,
-
-L<POSIX (3)/strcoll>
-
-L<POSIX (3)/strftime>
-
-L<POSIX (3)/strtod>,
-
-L<POSIX (3)/strxfrm>
+L<POSIX (3)/isalnum>, L<POSIX (3)/isalpha>, L<POSIX (3)/isdigit>,
+L<POSIX (3)/isgraph>, L<POSIX (3)/islower>, L<POSIX (3)/isprint>,
+L<POSIX (3)/ispunct>, L<POSIX (3)/isspace>, L<POSIX (3)/isupper>,
+L<POSIX (3)/isxdigit>, L<POSIX (3)/localeconv>, L<POSIX (3)/setlocale>,
+L<POSIX (3)/strcoll>, L<POSIX (3)/strftime>, L<POSIX (3)/strtod>,
+L<POSIX (3)/strxfrm>.
=head1 HISTORY
projects / p5sagit/p5-mst-13.2.git / blobdiff