C format strings are described in POSIX (IEEE P1003.1 2001),
section XSH 3 fprintf(), http://www.opengroup.org/onlinepubs/007
904975/functions/fprintf.html. See also the fprintf() manual
page, http://www.linuxvalley.it/encyclopedia/ldp/manpage/man3/pr
intf.3.php, http://informatik.fh-
wuerzburg.de/student/i510/man/printf.html. Although format
strings with positions that reorder arguments, such as "Only
%2$d bytes free on '%1$s'." which is semantically equivalent to
"'%s' has only %d bytes free." are a POSIX/XSI feature and not
specified by ISO C 99, translators can rely on this reordering
ability: On the few platforms where fprintf() etc. don't support
this feature natively, libintl.a or libintl.so provides
replacement functions, and GNU activates these replacement
functions automatically. As a special feature for Farsi
(Persian) and maybe Arabic, translators can insert an ‘I’ flag
into numeric format directives. For example, the "%d" can be
"%Id". The effect of this flag, on systems with GNU libc, is
that in th