Pspp has three ``working'' locales:
@itemize
-@item The local of the user interface.
-@item The local of the output.
-@item The local of the data. Only the character encoding is relevant.
+@item The locale of the user interface.
+@item The locale of the output.
+@item The locale of the data. Only the character encoding is relevant.
@end itemize
Each of these locales may, at different times take
@subsection The data locale
This locale is the one associated with the data being analysed with pspp.
The only important aspect of this locale is the character encoding.
-@footnote {It might also be desirable for the LC_COLLATE category to be used for the purposes of sorting data.}
+@footnote{It might also be desirable for the LC_COLLATE category to be used for the purposes of sorting data.}
The dictionary pertaining to the data contains a field denoting the encoding.
Any string data stored in a @union{value} will be encoded in the
dictionary's character set.
-
@section System files
@file{*.sav} files contain a field which is supposed to identify the encoding
of the data they contain (@pxref{Machine Integer Info Record}).
@section GUI
The psppire graphic user interface is written using the Gtk+ api, for which
all strings must be encoded in UTF8.
-All strings passed to the Gtk+/Glib library functions (except for filenames)
+All strings passed to the GTK+/GLib library functions (except for filenames)
must be UTF-8 encoded otherwise errors will occur.
Thus, for the purposes of the programming psppire, the user interface locale
should be assumed to be UTF8, even if setlocale and/or nl_langinfo
The GLib API has some special functions for dealing with filenames.
Strings returned from functions like gtk_file_chooser_dialog_get_name are not,
in general, encoded in UTF8, but in ``filename'' encoding.
-If that filename is passed to another Glib function which expects a filename,
+If that filename is passed to another GLib function which expects a filename,
no conversion is necessary.
If it's passed to a function for the purposes of displaying it (eg. in a
window's title-bar) it must be converted to UTF8 --- there is a special
function for this: g_filename_display_name or g_filename_basename.
-If however, a filename needs to be passed outside of Gtk/Glib (for example to fopen) it must be converted to the local system encoding.
+If however, a filename needs to be passed outside of GTK+/GLib (for example to fopen) it must be converted to the local system encoding.
@section Existing locale handling functions
longer required.
@end deftypefun
+In order to minimise the number of conversions required, and to simplify
+design, PSPP attempts to store all internal strings in UTF8 encoding.
+Thus, when reading system and portable files (or any other data source),
+the following items are immediately converted to UTF8 encoding:
+@itemize
+@item Variable names
+@item Variable labels
+@item Value labels
+@end itemize
+Conversely, when writing system files, these are converted back to the
+encoding of that system file.
-For example, in order to display a string variable's value in a label widget in the psppire gui one would use code similar to
-@example
-
-struct variable *var = /* assigned from somewhere */
-struct case c = /* from somewhere else */
-
-const union value *val = case_data (&c, var);
-
-char *utf8string = recode_string (UTF8, dict_get_encoding (dict), val->s,
- var_get_width (var));
-
-GtkWidget *entry = gtk_entry_new();
-gtk_entry_set_text (entry, utf8string);
-gtk_widget_show (entry);
-
-free (utf8string);
-
-@end example
+String data stored in union values are left in their original encoding.
+These will be converted by the data_in/data_out functions.