File: gawk.info,  Node: I18N Portability,  Prev: Printf Ordering,  Up: Translator i18n

13.4.3 'awk' Portability Issues
-------------------------------

'gawk''s internationalization features were purposely chosen to have as
little impact as possible on the portability of 'awk' programs that use
them to other versions of 'awk'.  Consider this program:

     BEGIN {
         TEXTDOMAIN = "guide"
         if (Test_Guide)   # set with -v
             bindtextdomain("/test/guide/messages")
         print _"don't panic!"
     }

As written, it won't work on other versions of 'awk'.  However, it is
actually almost portable, requiring very little change:

   * Assignments to 'TEXTDOMAIN' won't have any effect, because
     'TEXTDOMAIN' is not special in other 'awk' implementations.

   * Non-GNU versions of 'awk' treat marked strings as the concatenation
     of a variable named '_' with the string following it.(1)
     Typically, the variable '_' has the null string ('""') as its
     value, leaving the original string constant as the result.

   * By defining "dummy" functions to replace 'dcgettext()',
     'dcngettext()', and 'bindtextdomain()', the 'awk' program can be
     made to run, but all the messages are output in the original
     language.  For example:

          function bindtextdomain(dir, domain)
          {
              return dir
          }

          function dcgettext(string, domain, category)
          {
              return string
          }

          function dcngettext(string1, string2, number, domain, category)
          {
              return (number == 1 ? string1 : string2)
          }

   * The use of positional specifications in 'printf' or 'sprintf()' is
     _not_ portable.  To support 'gettext()' at the C level, many
     systems' C versions of 'sprintf()' do support positional
     specifiers.  But it works only if enough arguments are supplied in
     the function call.  Many versions of 'awk' pass 'printf' formats
     and arguments unchanged to the underlying C library version of
     'sprintf()', but only one format and argument at a time.  What
     happens if a positional specification is used is anybody's guess.
     However, because the positional specifications are primarily for
     use in _translated_ format strings, and because non-GNU 'awk's
     never retrieve the translated string, this should not be a problem
     in practice.

   ---------- Footnotes ----------

   (1) This is good fodder for an "Obfuscated 'awk'" contest.