initial import

manual/examples/rprintf.c

@@ -0,0 +1,52 @@
+#include <stdio.h>
+#include <printf.h>
+#include <stdarg.h>
+
+/*@group*/
+typedef struct
+  {
+    char *name;
+  } Widget;
+/*@end group*/
+
+int 
+print_widget (FILE *stream, const struct printf_info *info, va_list *app)
+{
+  Widget *w;
+  char *buffer;
+  int len;
+
+  /* Format the output into a string. */
+  w = va_arg (*app, Widget *);
+  len = asprintf (&buffer, "<Widget %p: %s>", w, w->name);
+  if (len == -1)
+    return -1;
+
+  /* Pad to the minimum field width and print to the stream. */
+  len = fprintf (stream, "%*s",
+		 (info->left ? - info->width : info->width),
+		 buffer);
+
+  /* Clean up and return. */
+  free (buffer);
+  return len;
+}
+
+
+int
+main (void)
+{
+  /* Make a widget to print. */
+  Widget mywidget;
+  mywidget.name = "mywidget";
+
+  /* Register the print function for widgets. */
+  register_printf_function ('W', print_widget, NULL); /* No arginfo.  */
+
+  /* Now print the widget. */
+  printf ("|%W|\n", &mywidget);
+  printf ("|%35W|\n", &mywidget);
+  printf ("|%-35W|\n", &mywidget);
+
+  return 0;
+}