PERLLOCALE(1) PERLLOCALE(1)
NAME
perllocale - Perl locale handling (internationalization and localization)
DESCRIPTION
Perl supports language-specific notions of data such as "is this a
letter", "what is the uppercase equivalent of this letter", and "which of
these letters comes first". These are important issues, especially for
languages other than English - but also for English: it would be very
naieve to think that A-Za-z defines all the "letters". Perl is also aware
that some character other than '.' may be preferred as a decimal point,
and that output date representations may be language-specific. The
process of making an application take account of its users' preferences
in such matters is called internationalization (often abbreviated as
i18n); telling such an application about a particular set of preferences
is known as localization (l10n).
Perl can understand language-specific data via the standardized (ISO C,
XPG4, POSIX 1.c) method called "the locale system". The locale system is
controlled per application using one pragma, one function call, and
several environment variables.
NOTE: This feature is new in Perl 5.004, and does not apply unless an
application specifically requests it - see the section on Backward
compatibility. The one exception is that write() now always uses the
current locale - see the section on NOTES.
PREPARING TO USE LOCALES
If Perl applications are to be able to understand and present your data
correctly according a locale of your choice, all of the following must be
true:
⊕ Your operating system must support the locale system. If it does,
you should find that the setlocale() function is a documented part of
its C library.
⊕ Definitions for the locales which you use must be installed. You, or
your system administrator, must make sure that this is the case. The
available locales, the location in which they are kept, and the
manner in which they are installed, vary from system to system. Some
systems provide only a few, hard-wired, locales, and do not allow
more to be added; others allow you to add "canned" locales provided
by the system supplier; still others allow you or the system
administrator to define and add arbitrary locales. (You may have to
ask your supplier to provide canned locales which are not delivered
with your operating system.) Read your system documentation for
further illumination.
⊕ Perl must believe that the locale system is supported. If it does,
perl -V:d_setlocale will say that the value for d_setlocale is
define.
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PERLLOCALE(1) PERLLOCALE(1)
If you want a Perl application to process and present your data according
to a particular locale, the application code should include the use
locale pragma (see the section on The use locale pragma) where
appropriate, and at least one of the following must be true:
⊕ The locale-determining environment variables (see the section on
ENVIRONMENT) must be correctly set up, either by yourself, or by the
person who set up your system account, at the time the application is
started.
⊕ The application must set its own locale using the method described in
the section on The setlocale function.
USING LOCALES
The use locale pragma
By default, Perl ignores the current locale. The use locale pragma tells
Perl to use the current locale for some operations:
⊕ The comparison operators (lt, le, cmp, ge, and gt) and the POSIX
string collation functions strcoll() and strxfrm() use LC_COLLATE.
sort() is also affected if it is used without an explicit comparison
function because it uses cmp by default.
Note: eq and ne are unaffected by the locale: they always perform a
byte-by-byte comparison of their scalar operands. What's more, if
cmp finds that its operands are equal according to the collation
sequence specified by the current locale, it goes on to perform a
byte-by-byte comparison, and only returns 0 (equal) if the operands
are bit-for-bit identical. If you really want to know whether two
strings - which eq and cmp may consider different - are equal as far
as collation in the locale is concerned, see the discussion in the
section on Category LC_COLLATE: Collation.
⊕ Regular expressions and case-modification functions (uc(), lc(),
ucfirst(), and lcfirst()) use LC_CTYPE
⊕ The formatting functions (printf(), sprintf() and write()) use
LC_NUMERIC
⊕ The POSIX date formatting function (strftime()) uses LC_TIME.
LC_COLLATE, LC_CTYPE, and so on, are discussed further in the section on
LOCALE CATEGORIES.
The default behavior returns with no locale or on reaching the end of the
enclosing block.
Note that the string result of any operation that uses locale information
is tainted, as it is possible for a locale to be untrustworthy. See the
section on SECURITY.
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PERLLOCALE(1) PERLLOCALE(1)
The setlocale function
You can switch locales as often as you wish at run time with the
POSIX::setlocale() function:
# This functionality not usable prior to Perl 5.004
require 5.004;
# Import locale-handling tool set from POSIX module.
# This example uses: setlocale -- the function call
# LC_CTYPE -- explained below
use POSIX qw(locale_h);
# query and save the old locale
$old_locale = setlocale(LC_CTYPE);
setlocale(LC_CTYPE, "fr_CA.ISO8859-1");
# LC_CTYPE now in locale "French, Canada, codeset ISO 8859-1"
setlocale(LC_CTYPE, "");
# LC_CTYPE now reset to default defined by LC_ALL/LC_CTYPE/LANG
# environment variables. See below for documentation.
# restore the old locale
setlocale(LC_CTYPE, $old_locale);
The first argument of setlocale() gives the category, the second the
locale. The category tells in what aspect of data processing you want to
apply locale-specific rules. Category names are discussed in the section
on LOCALE CATEGORIES and the section on ENVIRONMENT. The locale is the
name of a collection of customization information corresponding to a
particular combination of language, country or territory, and codeset.
Read on for hints on the naming of locales: not all systems name locales
as in the example.
If no second argument is provided, the function returns a string naming
the current locale for the category. You can use this value as the
second argument in a subsequent call to setlocale(). If a second
argument is given and it corresponds to a valid locale, the locale for
the category is set to that value, and the function returns the now-
current locale value. You can use this in a subsequent call to
setlocale(). (In some implementations, the return value may sometimes
differ from the value you gave as the second argument - think of it as an
alias for the value that you gave.)
As the example shows, if the second argument is an empty string, the
category's locale is returned to the default specified by the
corresponding environment variables. Generally, this results in a return
to the default which was in force when Perl started up: changes to the
environment made by the application after startup may or may not be
noticed, depending on the implementation of your system's C library.
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PERLLOCALE(1) PERLLOCALE(1)
If the second argument does not correspond to a valid locale, the locale
for the category is not changed, and the function returns undef.
For further information about the categories, consult the setlocale(3)
manpage. For the locales available in your system, also consult the
setlocale(3) manpage and see whether it leads you to the list of the
available locales (search for the SEE ALSO section). If that fails, try
the following command lines:
locale -a
nlsinfo
ls /usr/lib/nls/loc
ls /usr/lib/locale
ls /usr/lib/nls
and see whether they list something resembling these
en_US.ISO8859-1 de_DE.ISO8859-1 ru_RU.ISO8859-5
en_US de_DE ru_RU
en de ru
english german russian
english.iso88591 german.iso88591 russian.iso88595
Sadly, even though the calling interface for setlocale() has been
standardized, the names of the locales and the directories where the
configuration is, have not. The basic form of the name is
language_country/territory.codeset, but the latter parts are not always
present.
Two special locales are worth particular mention: "C" and "POSIX".
Currently these are effectively the same locale: the difference is mainly
that the first one is defined by the C standard and the second by the
POSIX standard. What they define is the default locale in which every
program starts in the absence of locale information in its environment.
(The default default locale, if you will.) Its language is (American)
English and its character codeset ASCII.
NOTE: Not all systems have the "POSIX" locale (not all systems are
POSIX-conformant), so use "C" when you need explicitly to specify this
default locale.
The localeconv function
The POSIX::localeconv() function allows you to get particulars of the
locale-dependent numeric formatting information specified by the current
LC_NUMERIC and LC_MONETARY locales. (If you just want the name of the
current locale for a particular category, use POSIX::setlocale() with a
single parameter - see the section on The setlocale function.)
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use POSIX qw(locale_h);
# Get a reference to a hash of locale-dependent info
$locale_values = localeconv();
# Output sorted list of the values
for (sort keys %$locale_values) {
printf "%-20s = %s\n", $_, $locale_values->{$_}
}
localeconv() takes no arguments, and returns a reference to a hash. The
keys of this hash are formatting variable names such as decimal_point and
thousands_sep; the values are the corresponding values. See the
localeconv entry in the POSIX (3) manpage for a longer example, which
lists all the categories an implementation might be expected to provide;
some provide more and others fewer, however. Note that you don't need
use locale: as a function with the job of querying the locale,
localeconv() always observes the current locale.
Here's a simple-minded example program which rewrites its command line
parameters as integers formatted correctly in the current locale:
# See comments in previous example
require 5.004;
use POSIX qw(locale_h);
# Get some of locale's numeric formatting parameters
my ($thousands_sep, $grouping) =
@{localeconv()}{'thousands_sep', 'grouping'};
# Apply defaults if values are missing
$thousands_sep = ',' unless $thousands_sep;
$grouping = 3 unless $grouping;
# Format command line params for current locale
for (@ARGV) {
$_ = int; # Chop non-integer part
1 while
s/(\d)(\d{$grouping}($|$thousands_sep))/$1$thousands_sep$2/;
print "$_";
}
print "\n";
LOCALE CATEGORIES
The subsections which follow describe basic locale categories. As well
as these, there are some combination categories which allow the
manipulation of more than one basic category at a time. See the section
on ENVIRONMENT for a discussion of these.
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Category LCCOLLATE: Collation
When in the scope of use locale, Perl looks to the LC_COLLATE environment
variable to determine the application's notions on the collation
(ordering) of characters. ('b' follows 'a' in Latin alphabets, but where
do 'a' and 'aa' belong?)
Here is a code snippet that will tell you what are the alphanumeric
characters in the current locale, in the locale order:
use locale;
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";
This machine-native collation (which is what you get unless use locale
has appeared earlier in the same block) must be used for sorting raw
binary data, whereas the locale-dependent collation of the first example
is useful for natural text.
As noted in the section on USING LOCALES, cmp compares according to the
current collation locale when use locale is in effect, but falls back to
a byte-by-byte comparison for strings which the locale says are equal.
You can use POSIX::strcoll() if you don't want this fall-back:
use POSIX qw(strcoll);
$equal_in_locale =
!strcoll("space and case ignored", "SpaceAndCaseIgnored");
$equal_in_locale will be true if the collation locale specifies a
dictionary-like ordering which ignores space characters completely, and
which folds case.
If you have a single string which you want to check for "equality in
locale" against several others, you might think you could gain a little
efficiency by using POSIX::strxfrm() in conjunction with eq:
use POSIX qw(strxfrm);
$xfrm_string = strxfrm("Mixed-case string");
print "locale collation ignores spaces\n"
if $xfrm_string eq strxfrm("Mixed-casestring");
print "locale collation ignores hyphens\n"
if $xfrm_string eq strxfrm("Mixedcase string");
print "locale collation ignores case\n"
if $xfrm_string eq strxfrm("mixed-case string");
strxfrm() takes a string and maps it into a transformed string for use in
byte-by-byte comparisons against other transformed strings during
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collation. "Under the hood", locale-affected Perl comparison operators
call strxfrm() for both their operands, then do a byte-by-byte comparison
of the transformed strings. By calling strxfrm() explicitly, and using a
non locale-affected comparison, the example attempts to save a couple of
transformations. In fact, it doesn't save anything: Perl magic (see the
section on Magic Variables in the perlguts manpage) creates the
transformed version of a string the first time it's needed in a
comparison, then keeps it around in case it's needed again. An example
rewritten the easy way with cmp runs just about as fast. It also copes
with null characters embedded in strings; if you call strxfrm() directly,
it treats the first null it finds as a terminator. And don't expect the
transformed strings it produces to be portable across systems - or even
from one revision of your operating system to the next. In short, don't
call strxfrm() directly: let Perl do it for you.
Note: use locale isn't shown in some of these examples, as it isn't
needed: strcoll() and strxfrm() exist only to generate locale-dependent
results, and so always obey the current LC_COLLATE locale.
Category LCCTYPE: Character Types
When in the scope of use locale, Perl obeys the LC_CTYPE locale setting.
This controls the application's notion of which characters are
alphabetic. This affects Perl's \w regular expression metanotation,
which stands for alphanumeric characters - that is, alphabetic and
numeric characters. (Consult the perlre manpage for more information
about regular expressions.) Thanks to LC_CTYPE, depending on your locale
setting, characters like 'ae', '`
d', 'ss', and 'o' may be understood as \w
characters.
The LC_CTYPE locale also provides the map used in translating characters
between lower and uppercase. This affects the case-mapping functions -
lc(), lcfirst, uc() and ucfirst(); case-mapping interpolation with \l,
\L, \u or <\U> in double-quoted strings and in s/// substitutions; and
case-independent regular expression pattern matching using the i
modifier.
Finally, LC_CTYPE affects the POSIX character-class test functions -
isalpha(), islower() and so on. For example, if you move from the "C"
locale to a 7-bit Scandinavian one, you may find - possibly to your
surprise - that "|" moves from the ispunct() class to isalpha().
Note: A broken or malicious LC_CTYPE locale definition may result in
clearly ineligible characters being considered to be alphanumeric by your
application. For strict matching of (unaccented) letters and digits -
for example, in command strings - locale-aware applications should use \w
inside a no locale block. See the section on SECURITY.
Category LCNUMERIC: Numeric Formatting
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When in the scope of use locale, Perl obeys the LC_NUMERIC locale
information, which controls application's idea of how numbers should be
formatted for human readability by the printf(), sprintf(), and write()
functions. String to numeric conversion by the POSIX::strtod() function
is also affected. In most implementations the only effect is to change
the character used for the decimal point - perhaps from '.' to ',':
these functions aren't aware of such niceties as thousands separation and
so on. (See the section on The localeconv function if you care about
these things.)
Note that output produced by print() is never affected by the current
locale: it is independent of whether use locale or 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
print "half five is $n\n"; # Locale-independent output
printf "half five is %g\n", $n; # Locale-dependent output
print "DECIMAL POINT IS COMMA\n"
if $n == (strtod("2,5"))[0]; # Locale-dependent conversion
Category LCMONETARY: Formatting of monetary amounts
The C standard defines the LC_MONETARY category, but no function 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
LC_MONETARY, you can query its contents - see the section on 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, though voluminous and complex, does not quite
meet your requirements: currency formatting is a hard nut to crack.
LCTIME
The output produced by POSIX::strftime(), which builds a formatted
human-readable date/time string, is affected by the current LC_TIME
locale. Thus, in a French locale, the output produced by the %B format
element (full month name) for the first month of the year would be
"janvier". Here's how to get a list of the long month names in the
current locale:
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use POSIX qw(strftime);
for (0..11) {
$long_month_name[$_] =
strftime("%B", 0, 0, 0, 1, $_, 96);
}
Note: use locale isn't needed in this example: as a function which exists
only to generate locale-dependent results, strftime() always obeys the
current LC_TIME locale.
Other categories
The remaining locale category, 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 which are not part of the standard Perl distribution.
SECURITY
While the main discussion of Perl security issues can be found in the
perlsec manpage, a discussion of Perl's locale handling would be
incomplete if it did not draw your attention to locale-dependent security
issues. Locales - particularly on systems which allow unprivileged users
to build their own locales - are untrustworthy. A malicious (or just
plain broken) locale can make a locale-aware application give unexpected
results. Here are a few possibilities:
⊕ Regular expression checks for safe file names or mail addresses using
\w may be spoofed by an LC_CTYPE locale which claims that characters
such as ">" and "|" are alphanumeric.
⊕ String interpolation with case-mapping, as in, say, $dest =
"C:\U$name.$ext", may produce dangerous results if a bogus LC_CTYPE
case-mapping table is in effect.
⊕ If the decimal point character in the LC_NUMERIC locale is
surreptitiously changed from a dot to a comma, 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.
⊕ A sneaky LC_COLLATE locale could result in the names of students with
"D" grades appearing ahead of those with "A"s.
⊕ An application which takes the trouble to use the information in
LC_MONETARY may format debits as if they were credits and vice versa
if that locale has been subverted. Or it make may make payments in
US dollars instead of Hong Kong dollars.
⊕ The date and day names in dates formatted by strftime() could be
manipulated to advantage by a malicious user able to subvert the
LC_DATE locale. ("Look - it says I wasn't in the building on
Sunday.")
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Such dangers are not peculiar to the locale system: any aspect of an
application's environment which may maliciously be modified presents
similar challenges. Similarly, they are not specific to Perl: any
programming language which allows you to write programs which take
account of their environment exposes you to these issues.
Perl cannot protect you from all of the possibilities shown in the
examples - there is no substitute for your own vigilance - but, when use
locale is in effect, Perl uses the tainting mechanism (see the perlsec
manpage) to mark string results which become locale-dependent, and which
may be untrustworthy in consequence. Here is a summary of the tainting
behavior of operators and functions which may be affected by the locale:
Comparison operators (lt, le, ge, gt and cmp):
Scalar true/false (or less/equal/greater) result is never tainted.
Case-mapping interpolation (with \l, \L, \u or <\U>)
Result string containing interpolated material is tainted if use
locale is in effect.
Matching operator (m//):
Scalar true/false result never tainted.
Subpatterns, either delivered as an array-context result, or as $1
etc. are tainted if use locale is in effect, and the subpattern
regular expression contains \w (to match an alphanumeric character),
\W (non-alphanumeric character), \s (white-space character), or \S
(non white-space character). The matched pattern variable, $&, $`
(pre-match), $' (post-match), and $+ (last match) are also tainted if
use locale is in effect and the regular expression contains \w, \W,
\s, or \S.
Substitution operator (s///):
Has the same behavior as the match operator. Also, the left operand
of =~ becomes tainted when use locale in effect, if it is modified as
a result of a substitution based on a regular expression match
involving \w, \W, \s, or \S; or of case-mapping with \l, \L,\u or
<\U>.
In-memory formatting function (sprintf()):
Result is tainted if "use locale" is in effect.
Output formatting functions (printf() and write()):
Success/failure result is never tainted.
Case-mapping functions (lc(), lcfirst(), uc(), ucfirst()):
Results are tainted if use locale is in effect.
strxfrm()):
POSIX locale-dependent functions (localeconv(), strcoll(), strftime(),
Results are never tainted.
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islower(), isprint(), ispunct(), isspace(), isupper(), isxdigit()):
POSIX character class tests (isalnum(), isalpha(), isdigit(), isgraph(),
True/false results are never tainted.
Three examples illustrate locale-dependent tainting. The first program,
which ignores its locale, won't run: a value taken directly from the
command line may not be used to name an output file when taint checks are
enabled.
#/usr/local/bin/perl -T
# Run with taint checking
# Command line sanity check omitted...
$tainted_output_file = shift;
open(F, ">$tainted_output_file")
or warn "Open of $untainted_output_file failed: $!\n";
The program can be made to run by "laundering" the tainted value through
a regular expression: the second example - which still ignores locale
information - runs, creating the file named on its command line if it
can.
#/usr/local/bin/perl -T
$tainted_output_file = shift;
$tainted_output_file =~ m%[\w/]+%;
$untainted_output_file = $&;
open(F, ">$untainted_output_file")
or warn "Open of $untainted_output_file failed: $!\n";
Compare this with a very similar program which is locale-aware:
#/usr/local/bin/perl -T
$tainted_output_file = shift;
use locale;
$tainted_output_file =~ m%[\w/]+%;
$localized_output_file = $&;
open(F, ">$localized_output_file")
or warn "Open of $localized_output_file failed: $!\n";
This third program fails to run because $& is tainted: it is the result
of a match involving \w when use locale is in effect.
ENVIRONMENT
PERL_BADLANG
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) is some way - or
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if you mistyped the name of a locale when you set up your
environment. If this environment variable is absent, or has
a value which does not evaluate to integer zero - that is "0"
or "" - Perl will complain about locale setting failures.
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, and you should investigate what the
problem is.
The following environment variables are not specific to Perl: They are
part of the standardized (ISO C, XPG4, POSIX 1.c) setlocale() method for
controlling an application's opinion on data.
LC_ALL LC_ALL is the "override-all" locale environment variable. If
it is set, it overrides all the rest of the locale
environment variables.
LC_CTYPE In the absence of LC_ALL, LC_CTYPE chooses the character type
locale. In the absence of both LC_ALL and LC_CTYPE, LANG
chooses the character type locale.
LC_COLLATE In the absence of LC_ALL, LC_COLLATE chooses the collation
(sorting) locale. In the absence of both LC_ALL and
LC_COLLATE, LANG chooses the collation locale.
LC_MONETARY In the absence of LC_ALL, LC_MONETARY chooses the monetary
formatting locale. In the absence of both LC_ALL and
LC_MONETARY, LANG chooses the monetary formatting locale.
LC_NUMERIC In the absence of LC_ALL, LC_NUMERIC chooses the numeric
format locale. In the absence of both LC_ALL and LC_NUMERIC,
LANG chooses the numeric format.
LC_TIME In the absence of LC_ALL, LC_TIME chooses the date and time
formatting locale. In the absence of both LC_ALL and
LC_TIME, LANG chooses the date and time formatting locale.
LANG LANG is the "catch-all" locale environment variable. If it is
set, it is used as the last resort after the overall LC_ALL
and the category-specific LC_....
NOTES
Backward compatibility
Versions of Perl prior to 5.004 mostly ignored locale information,
generally behaving as if something similar to the "C" locale (see the
section on The setlocale function) was always in force, even if the
program environment suggested otherwise. By default, Perl still behaves
this way so as to maintain backward compatibility. If you want a Perl
application to pay attention to locale information, you must use the use
locale pragma (see the section on The use locale Pragma) to instruct it
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to do so.
Versions of Perl from 5.002 to 5.003 did use the LC_CTYPE information if
that was available, that is, \w did understand what are the letters
according to the locale environment variables. The problem was that the
user had no control over the feature: if the C library supported
locales, Perl used them.
I18N:Collate obsolete
In versions of Perl prior to 5.004 per-locale collation was possible
using the I18N::Collate library module. This module is now mildly
obsolete and should be avoided in new applications. The LC_COLLATE
functionality is now integrated into the Perl core language: One can use
locale-specific scalar data completely normally with use locale, so there
is no longer any need to juggle with the scalar references of
I18N::Collate.
Sort speed and memory use impacts
Comparing and sorting by locale is usually slower than the default
sorting; slow-downs of two to four times have been observed. It will
also consume more memory: once a Perl scalar variable has participated in
any string comparison or sorting operation obeying the locale collation
rules, it will take 3-15 times more memory than before. (The exact
multiplier depends on the string's contents, the operating system and the
locale.) These downsides are dictated more by the operating system's
implementation of the locale system than by Perl.
write() and LC_NUMERIC
Formats are the only part of Perl which unconditionally use information
from a program's locale; if a program's environment specifies an
LC_NUMERIC locale, it is always used to specify the decimal point
character in formatted output. Formatted output cannot be controlled by
use locale because the pragma is tied to the block structure of the
program, and, for historical reasons, formats exist outside that block
structure.
Freely available locale definitions
There is a large collection of locale definitions at
ftp://dkuug.dk/i18n/WG15-collection. You should be aware that it is
unsupported, and is not claimed to be fit for any purpose. If your
system allows the installation of arbitrary locales, you may find the
definitions useful as they are, or as a basis for the development of your
own locales.
I18n and l10n
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"Internationalization" is often abbreviated as i18n because its first and
last letters are separated by eighteen others. (You may guess why the
internalin ... internaliti ... i18n tends to get abbreviated.) In the
same way, "localization" is often abbreviated to l10n.
An imperfect standard
Internationalization, as defined in the C and POSIX standards, can be
criticized as incomplete, ungainly, and having too large a granularity.
(Locales apply to a whole process, when it would arguably be more useful
to have them apply to a single thread, window group, or whatever.) They
also have a tendency, like standards groups, to divide the world into
nations, when we all know that the world can equally well be divided into
bankers, bikers, gamers, and so on. But, for now, it's the only standard
we've got. This may be construed as a bug.
BUGS
Broken systems
In certain system environments the operating system's locale support 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 use
locale is in effect. When confronted with such a system, please report
in excruciating detail to <perlbug@perl.com>, and complain to your
vendor: maybe some bug fixes exist for these problems in your operating
system. Sometimes such bug fixes are called an operating system upgrade.
SEE ALSO
the isalnum entry in the POSIX (3) manpage, the isalpha entry in the
POSIX (3) manpage, the isdigit entry in the POSIX (3) manpage, the
isgraph entry in the POSIX (3) manpage, the islower entry in the POSIX
(3) manpage, the isprint entry in the POSIX (3) manpage, the ispunct
entry in the POSIX (3) manpage, the isspace entry in the POSIX (3)
manpage, the isupper entry in the POSIX (3) manpage, the isxdigit entry
in the POSIX (3) manpage, the localeconv entry in the POSIX (3) manpage,
the setlocale entry in the POSIX (3) manpage, the strcoll entry in the
POSIX (3) manpage, the strftime entry in the POSIX (3) manpage, the
strtod entry in the POSIX (3) manpage, the strxfrm entry in the POSIX (3)
manpage
HISTORY
Jarkko Hietaniemi's original perli18n.pod heavily hacked by Dominic
Dunlop, assisted by the perl5-porters.
Last update: Wed Jan 22 11:04:58 EST 1997
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