manpage: improve locale setup in example .xsession (Thanks Harald König)

Harald mentioned he was surprised about the locales we recommend in the
.xsession example, so I’ve re-investigated.

Here is the test program I have used:

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

    int main() {
        /* SUSv2 setlocale(3) says:
         * Internationalised programs must call setlocale() to initiate
         * a specific language operation. This can be done by calling
         * setlocale() as follows: */
        setlocale(LC_ALL, "");

        printf("LC_NUMERIC is %s\n", setlocale(LC_NUMERIC, NULL));
    }

Then, I have unset LANG and LC_*:

    midna /tmp $ env | grep LANG
    midna /tmp $ env | grep LC
    midna /tmp $

Now, observe that LC_ALL overwrites all specific LC variables:

    midna /tmp $ LC_ALL=de_DE.UTF-8 LC_NUMERIC=en_DK.UTF-8 ./localetest
    LC_NUMERIC is de_DE.UTF-8

However, LANG does not:

    midna /tmp $ LANG=de_DE.UTF-8 ./localetest
    LC_NUMERIC is de_DE.UTF-8
    midna /tmp $ LANG=de_DE.UTF-8 LC_NUMERIC=en_DK.UTF-8 ./localetest
    LC_NUMERIC is en_DK.UTF-8

This is consistent with what perldoc perllocale says:
http://perldoc.perl.org/perllocale.html#ENVIRONMENT

diff --git a/man/i3.man b/man/i3.man
index c20e39da4da4a42e171915d9a7c0f07f24a13d1a..c2b9039ca92c3ea08814b5633793a17b29c60914 100644 (file)
--- a/man/i3.man
+++ b/man/i3.man
@@ -262,19 +262,15 @@ xset -b
 # Enable zapping (C-A-<Bksp> kills X)
 setxkbmap -option terminate:ctrl_alt_bksp
 
-# Enforce correct locales from the beginning
-unset LC_COLLATE
-export LC_CTYPE=de_DE.UTF-8
-export LC_TIME=de_DE.UTF-8
-export LC_NUMERIC=de_DE.UTF-8
-export LC_MONETARY=de_DE.UTF-8
+# Enforce correct locales from the beginning:
+# LC_ALL is unset since it overwrites everything
+# LANG=de_DE.UTF-8 is used, except for:
+# LC_MESSAGES=C never translates program output
+# LC_TIME=en_DK leads to yyyy-mm-dd hh:mm date/time output
+unset LC_ALL
+export LANG=de_DE.UTF-8
 export LC_MESSAGES=C
-export LC_PAPER=de_DE.UTF-8
-export LC_NAME=de_DE.UTF-8
-export LC_ADDRESS=de_DE.UTF-8
-export LC_TELEPHONE=de_DE.UTF-8
-export LC_MEASUREMENT=de_DE.UTF-8
-export LC_IDENTIFICATION=de_DE.UTF-8
+export LC_TIME=en_DK.UTF-8
 
 # Use XToolkit in java applications
 export AWT_TOOLKIT=XToolkit