gettext: PO Header Entry API

 
 9.13.5 PO Header Entry API
 --------------------------
 
    The following functions provide an interface to extract and
 manipulate the header entry (⇒Header Entry) from a file loaded in
 memory.  The meta information must be written back into the domain
 message with the empty string as ‘msgid’.
 
  -- Function: const char * po_file_domain_header (po_file_t FILE,
           const char *DOMAIN)
      Returns the header entry of a domain from FILE, a PO file loaded in
      memory.  The value ‘NULL’ provided as DOMAIN denotes the default
      domain.  Returns ‘NULL’ if there is no header entry.
 
  -- Function: char * po_header_field (const char *HEADER,
           const char *FIELD)
      Returns the value of FIELD in the HEADER entry.  The return value
      is either a freshly allocated string, to be freed by the caller, or
      ‘NULL’.
 
  -- Function: char * po_header_set_field (const char *HEADER,
           const char *FIELD, const char *VALUE)
      Returns a freshly allocated string which contains the entry from
      HEADER with FIELD set to VALUE.  The field is added if necessary.