10.4.3 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,
since 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.(57) 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, since the positional specifications are primarily for use in
translated format strings, and since non-GNU awks never
retrieve the translated string, this should not be a problem in practice.
