Adding complications: program upgrade

The previous section presented a simple example of how Oriya language support could be added to a C program. Like all programs, we might now wish to further enhance it. For example, we could include a greeting to the user by adding another printf statement after the first one. Our new hello.c source code might look like this:

1    #include <libintl.h>
2    #include <locale.h>
3    #include <stdio.h>
4    #include <stdlib.h>
5    int main(void)
6    {
7      setlocale( LC_ALL, "" );
8      bindtextdomain( "hello", "/usr/share/locale" );
9      textdomain( "hello" );
10      printf( gettext( "Hello, world!\n" ) );
11      printf( gettext( "How are you\n" ) );
12      exit(0);
13    }

For such a small change, it would be simple enough to just repeat the above cycle of extracting the relevant English text, translating it to Oriya, and preparing a new message catalog. We can even simplify the work by cutting and pasting most of the old oriya.po file into the new one. However, real programs will have thousands of such strings, and we would like to be able to translate only the changed strings, and have the gettext utilities handle the drudgery of combining the new translations with the old ones. This is indeed possible.