1 files changed, 119 insertions, 0 deletions
diff --git a/examples/hist_erasedups.c b/examples/hist_erasedups.c
new file mode 100644
index 0000000..2ecee89
--- /dev/null
+++ b/examples/hist_erasedups.c
@@ -0,0 +1,119 @@
+/* hist_erasedups -- remove all duplicate entries from history file */
+
+/* Copyright (C) 2011 Free Software Foundation, Inc.
+
+   This file is part of the GNU Readline Library (Readline), a library for
+   reading lines of text with interactive input and history editing.
+
+   Readline is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   Readline is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with Readline.  If not, see <http://www.gnu.org/licenses/>.
+*/
+#ifndef READLINE_LIBRARY
+#define READLINE_LIBRARY 1
+#endif
+
+#include <unistd.h>
+#include <stdlib.h>
+#include <stdio.h>
+
+#ifdef READLINE_LIBRARY
+#  include "history.h"
+#else
+#  include <readline/history.h>
+#endif
+
+#include <string.h>
+
+#define STREQ(a, b) ((a)[0] == (b)[0] && strcmp(a, b) == 0)
+#define STREQN(a, b, n) ((n == 0) ? (1) \
+                                  : ((a)[0] == (b)[0] && strncmp(a, b, n) == 0))
+
+static void
+usage()
+{
+  fprintf (stderr, "hist_erasedups: usage: hist_erasedups [-t] [filename]\n");
+  exit (2);
+}
+
+int
+main (argc, argv)
+     int argc;
+     char **argv;
+{
+  char *fn;
+  int r;
+
+  while ((r = getopt (argc, argv, "t")) != -1)
+    {
+      switch (r)
+	{
+	case 't':
+	  history_write_timestamps = 1;
+	  break;
+	default:
+	  usage ();
+	}
+    }
+  argv += optind;
+  argc -= optind;
+
+  fn = argc ? argv[0] : getenv ("HISTFILE");
+  if (fn == 0)
+    {
+      fprintf (stderr, "hist_erasedups: no history file\n");
+      usage ();
+    }
+
+  if ((r = read_history (fn)) != 0)
+    {
+      fprintf (stderr, "hist_erasedups: read_history: %s: %s\n", fn, strerror (r));
+      exit (1);
+    }
+
+  hist_erasedups ();
+
+  if ((r = write_history (fn)) != 0)
+    {
+      fprintf (stderr, "hist_erasedups: write_history: %s: %s\n", fn, strerror (r));
+      exit (1);
+    }
+
+  exit (0);
+}
+
+int
+hist_erasedups ()
+{
+  int r, n;
+  HIST_ENTRY *h, *temp;
+
+  using_history ();
+  while (h = previous_history ())
+    {
+      r = where_history ();
+      for (n = 0; n < r; n++)
+	{
+	  temp = history_get (n+history_base);
+	  if (STREQ (h->line, temp->line))
+	    {
+	      remove_history (n);
+	      r--;			/* have to get one fewer now */
+	      n--;			/* compensate for above increment */
+	      history_offset--;		/* moving backwards in history list */
+	    }
+	}
+    }
+  using_history ();
+
+  return r;
+}