dgettext() applies domainname to the currently active LC_MESSAGE locale. This usage is equivalent in syntax and meaning to the textdomain() function's application of domainname, except that the selection of the domain in dgettext() is valid only for the duration of the call.
a NULL-terminated string to be matched in the catalogue with respect to a specific domain and the current locale.
On success of a msgid query, the translated NULL-terminated string is returned. On error, the original msgid is returned. The length of the string returned is undetermined until dgettext() is called.
gettext, dgettext, ngettext, dngettext, dcgettext, dcngettext, textdomain, bindtextdomain, bind_textdomain_codeset