I think I don’t understand anything anymore. Look:

~$ locale
LANG=hu_HU.UTF-8
LC_CTYPE="hu_HU.UTF-8"
LC_NUMERIC="hu_HU.UTF-8"
LC_TIME="hu_HU.UTF-8"
LC_COLLATE="hu_HU.UTF-8"
LC_MONETARY="hu_HU.UTF-8"
LC_MESSAGES="hu_HU.UTF-8"
LC_PAPER="hu_HU.UTF-8"
LC_NAME="hu_HU.UTF-8"
LC_ADDRESS="hu_HU.UTF-8"
LC_TELEPHONE="hu_HU.UTF-8"
LC_MEASUREMENT="hu_HU.UTF-8"
LC_IDENTIFICATION="hu_HU.UTF-8"
LC_ALL=

~$ perl -e 'use POSIX qw(setlocale LC_ALL); print setlocale(LC_ALL);' 
+## Print the current locale
LC_CTYPE=hu_HU.UTF-8;LC_NUMERIC=C;LC_TIME=hu_HU.UTF-8;LC_COLLATE=hu_HU
+.UTF-8;LC_MONETARY=hu_HU.UTF-8;LC_MESSAGES=hu_HU.UTF-8;LC_PAPER=hu_HU
+.UTF-8;LC_NAME=hu_HU.UTF-8;LC_ADDRESS=hu_HU.UTF-8;LC_TELEPHONE=hu_HU.
+UTF-8;LC_MEASUREMENT=hu_HU.UTF-8;LC_IDENTIFICATION=hu_HU.UTF-8
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Why is everything set except for LC_NUMERIC? Why is anything set? I never asked for this...

Update: C does the following:

#include <stdio.h>
#include <locale.h>

int main() {
        printf("%s\n", setlocale(LC_ALL, NULL));
        setlocale(LC_ALL, "");
        printf("%s\n", setlocale(LC_ALL, NULL));
        return 0;
}
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~$ ./localetest                  
C
hu_HU.UTF-8
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