diff --git a/include/cdio/cdio.h b/include/cdio/cdio.h
index 697f824b..c99d46df 100644
--- a/include/cdio/cdio.h
+++ b/include/cdio/cdio.h
@@ -1,5 +1,5 @@
 /* -*- c -*-
-    $Id: cdio.h,v 1.20 2003/09/20 12:34:02 rocky Exp $
+    $Id: cdio.h,v 1.21 2003/09/25 09:38:15 rocky Exp $
 
     Copyright (C) 2001 Herbert Valerio Riedel <hvr@gnu.org>
     Copyright (C) 2003 Rocky Bernstein <rocky@panix.com>
@@ -130,6 +130,15 @@ extern "C" {
   */
   char * cdio_get_default_device (const CdIo *obj);
 
+  /*!
+    Return the media catalog number MCN from the CD or NULL if there is none or
+    we don't have the ability to get it.
+
+    Note: string is malloc'd so caller has to free() the returned
+    string when done with it.
+  */
+  char *cdio_get_mcn (const CdIo *obj);
+
   /*!
     Return a string containing the name of the driver in use.
     if CdIo is NULL (we haven't initialized a specific device driver), 
diff --git a/lib/_cdio_bincue.c b/lib/_cdio_bincue.c
index 2caecd37..6597abb2 100644
--- a/lib/_cdio_bincue.c
+++ b/lib/_cdio_bincue.c
@@ -1,5 +1,5 @@
 /*
-    $Id: _cdio_bincue.c,v 1.29 2003/09/20 12:34:02 rocky Exp $
+    $Id: _cdio_bincue.c,v 1.30 2003/09/25 09:38:16 rocky Exp $
 
     Copyright (C) 2001 Herbert Valerio Riedel <hvr@gnu.org>
     Copyright (C) 2002,2003 Rocky Bernstein <rocky@panix.com>
@@ -24,7 +24,7 @@
    (*.cue).
 */
 
-static const char _rcsid[] = "$Id: _cdio_bincue.c,v 1.29 2003/09/20 12:34:02 rocky Exp $";
+static const char _rcsid[] = "$Id: _cdio_bincue.c,v 1.30 2003/09/25 09:38:16 rocky Exp $";
 
 #include "cdio_assert.h"
 #include "cdio_private.h"
@@ -95,7 +95,7 @@ typedef struct {
 } _img_private_t;
 
 static bool     _cdio_image_read_cue (_img_private_t *_obj);
-static uint32_t _cdio_stat_size (void *user_data);
+static uint32_t _cdio_stat_size (void *env);
 
 /*!
   Initialize image structures.
@@ -168,9 +168,9 @@ _cdio_init (_img_private_t *_obj)
   information in each sector.
 */
 static off_t
-_cdio_lseek (void *user_data, off_t offset, int whence)
+_cdio_lseek (void *env, off_t offset, int whence)
 {
-  _img_private_t *_obj = user_data;
+  _img_private_t *_obj = env;
 
   /* real_offset is the real byte offset inside the disk image
      The number below was determined empirically. I'm guessing
@@ -215,9 +215,9 @@ _cdio_lseek (void *user_data, off_t offset, int whence)
    boundaries.
 */
 static ssize_t
-_cdio_read (void *user_data, void *data, size_t size)
+_cdio_read (void *env, void *data, size_t size)
 {
-  _img_private_t *_obj = user_data;
+  _img_private_t *_obj = env;
   char buf[CDIO_CD_FRAMESIZE_RAW] = { 0, };
   char *p = data;
   ssize_t final_size=0;
@@ -266,9 +266,9 @@ _cdio_read (void *user_data, void *data, size_t size)
    Return the size of the CD in logical block address (LBA) units.
  */
 static uint32_t 
-_cdio_stat_size (void *user_data)
+_cdio_stat_size (void *env)
 {
-  _img_private_t *_obj = user_data;
+  _img_private_t *_obj = env;
   long size;
   int blocksize = _obj->sector_2336 
     ? M2RAW_SECTOR_SIZE : CDIO_CD_FRAMESIZE_RAW;
@@ -463,10 +463,10 @@ _cdio_image_read_cue (_img_private_t *_obj)
    from lsn. Returns 0 if no error. 
  */
 static int
-_cdio_read_audio_sectors (void *user_data, void *data, lsn_t lsn, 
+_cdio_read_audio_sectors (void *env, void *data, lsn_t lsn, 
 			  unsigned int nblocks)
 {
-  _img_private_t *_obj = user_data;
+  _img_private_t *_obj = env;
   int ret;
 
   _cdio_init (_obj);
@@ -499,10 +499,10 @@ _cdio_read_audio_sectors (void *user_data, void *data, lsn_t lsn,
    from lsn. Returns 0 if no error. 
  */
 static int
-_cdio_read_mode2_sector (void *user_data, void *data, lsn_t lsn, 
+_cdio_read_mode2_sector (void *env, void *data, lsn_t lsn, 
 			 bool mode2_form2)
 {
-  _img_private_t *_obj = user_data;
+  _img_private_t *_obj = env;
   int ret;
   char buf[CDIO_CD_FRAMESIZE_RAW] = { 0, };
   int blocksize = _obj->sector_2336 
@@ -535,10 +535,10 @@ _cdio_read_mode2_sector (void *user_data, void *data, lsn_t lsn,
    Returns 0 if no error. 
  */
 static int
-_cdio_read_mode2_sectors (void *user_data, void *data, uint32_t lsn, 
+_cdio_read_mode2_sectors (void *env, void *data, uint32_t lsn, 
 		     bool mode2_form2, unsigned int nblocks)
 {
-  _img_private_t *_obj = user_data;
+  _img_private_t *_obj = env;
   int i;
   int retval;
 
@@ -567,9 +567,9 @@ _cdio_read_mode2_sectors (void *user_data, void *data, uint32_t lsn,
   Set the device to use in I/O operations.
 */
 static int
-_cdio_set_arg (void *user_data, const char key[], const char value[])
+_cdio_set_arg (void *env, const char key[], const char value[])
 {
-  _img_private_t *_obj = user_data;
+  _img_private_t *_obj = env;
 
   if (!strcmp (key, "source"))
     {
@@ -608,9 +608,9 @@ _cdio_set_arg (void *user_data, const char key[], const char value[])
   Return the value associated with the key "arg".
 */
 static const char *
-_cdio_get_arg (void *user_data, const char key[])
+_cdio_get_arg (void *env, const char key[])
 {
-  _img_private_t *_obj = user_data;
+  _img_private_t *_obj = env;
 
   if (!strcmp (key, "source")) {
     return _obj->gen.source_name;
@@ -634,9 +634,9 @@ cdio_get_default_device_bincue(void)
   CDIO_INVALID_TRACK is returned on error.
 */
 static track_t
-_cdio_get_first_track_num(void *user_data) 
+_cdio_get_first_track_num(void *env) 
 {
-  _img_private_t *_obj = user_data;
+  _img_private_t *_obj = env;
   
   _cdio_init (_obj);
 
@@ -650,9 +650,9 @@ _cdio_get_first_track_num(void *user_data)
   CDIO_INVALID_TRACK is returned on error.
 */
 static track_t
-_cdio_get_num_tracks(void *user_data) 
+_cdio_get_num_tracks(void *env) 
 {
-  _img_private_t *_obj = user_data;
+  _img_private_t *_obj = env;
   _cdio_init (_obj);
 
   return _obj->have_cue && _obj->total_tracks > 0 ? _obj->total_tracks : 1;
@@ -663,9 +663,9 @@ _cdio_get_num_tracks(void *user_data)
   CDIO_INVALID_TRACK is returned on error.
 */
 static track_format_t
-_cdio_get_track_format(void *user_data, track_t track_num) 
+_cdio_get_track_format(void *env, track_t track_num) 
 {
-  _img_private_t *_obj = user_data;
+  _img_private_t *_obj = env;
   
   if (!_obj->gen.init) _cdio_init(_obj);
 
@@ -684,9 +684,9 @@ _cdio_get_track_format(void *user_data, track_t track_num)
   FIXME: there's gotta be a better design for this and get_track_format?
 */
 static bool
-_cdio_get_track_green(void *user_data, track_t track_num) 
+_cdio_get_track_green(void *env, track_t track_num) 
 {
-  _img_private_t *_obj = user_data;
+  _img_private_t *_obj = env;
   
   if (!_obj->gen.init) _cdio_init(_obj);
 
@@ -704,9 +704,9 @@ _cdio_get_track_green(void *user_data, track_t track_num)
   1 is returned on error.
 */
 static lba_t
-_cdio_get_track_lba(void *user_data, track_t track_num)
+_cdio_get_track_lba(void *env, track_t track_num)
 {
-  _img_private_t *_obj = user_data;
+  _img_private_t *_obj = env;
   _cdio_init (_obj);
 
   if (track_num == CDIO_CDROM_LEADOUT_TRACK) track_num = _obj->total_tracks+1;
@@ -725,9 +725,9 @@ _cdio_get_track_lba(void *user_data, track_t track_num)
 
 */
 static bool
-_cdio_get_track_msf(void *user_data, track_t track_num, msf_t *msf)
+_cdio_get_track_msf(void *env, track_t track_num, msf_t *msf)
 {
-  _img_private_t *_obj = user_data;
+  _img_private_t *_obj = env;
   _cdio_init (_obj);
 
   if (NULL == msf) return false;
@@ -816,6 +816,7 @@ cdio_open_common (_img_private_t **_data)
     .get_arg            = _cdio_get_arg,
     .get_default_device = cdio_get_default_device_bincue,
     .get_first_track_num= _cdio_get_first_track_num,
+    .get_mcn            = NULL,
     .get_num_tracks     = _cdio_get_num_tracks,
     .get_track_format   = _cdio_get_track_format,
     .get_track_green    = _cdio_get_track_green,
diff --git a/lib/_cdio_bsdi.c b/lib/_cdio_bsdi.c
index 6655d394..160db0f3 100644
--- a/lib/_cdio_bsdi.c
+++ b/lib/_cdio_bsdi.c
@@ -1,5 +1,5 @@
 /*
-    $Id: _cdio_bsdi.c,v 1.12 2003/09/20 12:34:02 rocky Exp $
+    $Id: _cdio_bsdi.c,v 1.13 2003/09/25 09:38:16 rocky Exp $
 
     Copyright (C) 2001 Herbert Valerio Riedel <hvr@gnu.org>
     Copyright (C) 2002,2003 Rocky Bernstein <rocky@panix.com>
@@ -27,7 +27,7 @@
 # include "config.h"
 #endif
 
-static const char _rcsid[] = "$Id: _cdio_bsdi.c,v 1.12 2003/09/20 12:34:02 rocky Exp $";
+static const char _rcsid[] = "$Id: _cdio_bsdi.c,v 1.13 2003/09/25 09:38:16 rocky Exp $";
 
 #include <cdio/sector.h>
 #include <cdio/util.h>
@@ -502,6 +502,7 @@ cdio_open_bsdi (const char *source_name)
     .get_arg            = _cdio_get_arg,
     .get_default_device = cdio_get_default_device_bsdi,
     .get_first_track_num= _cdio_get_first_track_num,
+    .get_mcn            = NULL, 
     .get_num_tracks     = _cdio_get_num_tracks,
     .get_track_format   = _cdio_get_track_format,
     .get_track_green    = _cdio_get_track_green,
diff --git a/lib/_cdio_freebsd.c b/lib/_cdio_freebsd.c
index 2575cd8b..0625bcd8 100644
--- a/lib/_cdio_freebsd.c
+++ b/lib/_cdio_freebsd.c
@@ -1,5 +1,5 @@
 /*
-    $Id: _cdio_freebsd.c,v 1.15 2003/09/01 15:11:36 rocky Exp $
+    $Id: _cdio_freebsd.c,v 1.16 2003/09/25 09:38:16 rocky Exp $
 
     Copyright (C) 2003 Rocky Bernstein <rocky@panix.com>
 
@@ -27,7 +27,7 @@
 # include "config.h"
 #endif
 
-static const char _rcsid[] = "$Id: _cdio_freebsd.c,v 1.15 2003/09/01 15:11:36 rocky Exp $";
+static const char _rcsid[] = "$Id: _cdio_freebsd.c,v 1.16 2003/09/25 09:38:16 rocky Exp $";
 
 #include <cdio/sector.h>
 #include <cdio/util.h>
@@ -118,14 +118,15 @@ _read_mode2 (int fd, void *buf, lba_t lba, unsigned int nblocks,
    Returns 0 if no error. 
  */
 static int
-_cdio_read_audio_sector (void *user_data, void *data, lsn_t lsn)
+_cdio_read_audio_sectors (void *env, void *data, lsn_t lsn
+			  unsigned int nblocks)
 {
   unsigned char buf[CDIO_CD_FRAMESIZE_RAW] = { 0, };
 
   struct cdrom_cdda cdda;
 
   cdda.cdda_addr = frame;
-  cdda.cdda_length = 1;
+  cdda.cdda_length = nblocks;
   cdda.cdda_data = buf;
   cdda.cdda_subcode = CDROM_DA_NO_SUBCODE;
 
@@ -144,14 +145,14 @@ _cdio_read_audio_sector (void *user_data, void *data, lsn_t lsn)
    from lsn. Returns 0 if no error. 
  */
 static int
-_cdio_read_mode2_sector (void *user_data, void *data, lsn_t lsn, 
+_cdio_read_mode2_sector (void *env, void *data, lsn_t lsn, 
 		    bool mode2_form2)
 {
   char buf[M2RAW_SECTOR_SIZE] = { 0, };
   struct cdrom_msf *msf = (struct cdrom_msf *) &buf;
   msf_t _msf;
 
-  _img_private_t *_obj = user_data;
+  _img_private_t *_obj = env;
 
   cdio_lba_to_msf (cdio_lsn_to_lba(lsn), &_msf);
   msf->cdmsf_min0 = from_bcd8(_msf.m);
@@ -205,10 +206,10 @@ _cdio_read_mode2_sector (void *user_data, void *data, lsn_t lsn,
    Returns 0 if no error. 
  */
 static int
-_cdio_read_mode2_sectors (void *user_data, void *data, lsn_t lsn, 
+_cdio_read_mode2_sectors (void *env, void *data, lsn_t lsn, 
 		     bool mode2_form2, unsigned int nblocks)
 {
-  _img_private_t *_obj = user_data;
+  _img_private_t *_obj = env;
   int i;
   int retval;
 
@@ -234,9 +235,9 @@ _cdio_read_mode2_sectors (void *user_data, void *data, lsn_t lsn,
    Return the size of the CD in logical block address (LBA) units.
  */
 static uint32_t 
-_cdio_stat_size (void *user_data)
+_cdio_stat_size (void *env)
 {
-  _img_private_t *_obj = user_data;
+  _img_private_t *_obj = env;
 
   struct ioc_read_toc_single_entry tocent;
   uint32_t size;
@@ -258,9 +259,9 @@ _cdio_stat_size (void *user_data)
   Set the key "arg" to "value" in source device.
 */
 static int
-_cdio_set_arg (void *user_data, const char key[], const char value[])
+_cdio_set_arg (void *env, const char key[], const char value[])
 {
-  _img_private_t *_obj = user_data;
+  _img_private_t *_obj = env;
 
   if (!strcmp (key, "source"))
     {
@@ -320,9 +321,9 @@ _cdio_read_toc (_img_private_t *_obj)
   Eject media. Return 1 if successful, 0 otherwise.
  */
 static int 
-_cdio_eject_media (void *user_data) {
+_cdio_eject_media (void *env) {
 
-  _img_private_t *_obj = user_data;
+  _img_private_t *_obj = env;
   int ret=2;
   int status;
   int fd;
@@ -346,9 +347,9 @@ _cdio_eject_media (void *user_data) {
   Return the value associated with the key "arg".
 */
 static const char *
-_cdio_get_arg (void *user_data, const char key[])
+_cdio_get_arg (void *env, const char key[])
 {
-  _img_private_t *_obj = user_data;
+  _img_private_t *_obj = env;
 
   if (!strcmp (key, "source")) {
     return _obj->gen.source_name;
@@ -368,9 +369,9 @@ _cdio_get_arg (void *user_data, const char key[])
   CDIO_INVALID_TRACK is returned on error.
 */
 static track_t
-_cdio_get_first_track_num(void *user_data) 
+_cdio_get_first_track_num(void *env) 
 {
-  _img_private_t *_obj = user_data;
+  _img_private_t *_obj = env;
   
   if (!_obj->toc_init) _cdio_read_toc (_obj) ;
 
@@ -382,9 +383,9 @@ _cdio_get_first_track_num(void *user_data)
   CDIO_INVALID_TRACK is returned on error.
 */
 static track_t
-_cdio_get_num_tracks(void *user_data) 
+_cdio_get_num_tracks(void *env) 
 {
-  _img_private_t *_obj = user_data;
+  _img_private_t *_obj = env;
   
   if (!_obj->toc_init) _cdio_read_toc (_obj) ;
 
@@ -395,9 +396,9 @@ _cdio_get_num_tracks(void *user_data)
   Get format of track. 
 */
 static track_format_t
-_cdio_get_track_format(void *user_data, track_t track_num) 
+_cdio_get_track_format(void *env, track_t track_num) 
 {
-  _img_private_t *_obj = user_data;
+  _img_private_t *_obj = env;
   
   if (!_obj->toc_init) _cdio_read_toc (_obj) ;
 
@@ -425,9 +426,9 @@ _cdio_get_track_format(void *user_data, track_t track_num)
   FIXME: there's gotta be a better design for this and get_track_format?
 */
 static bool
-_cdio_get_track_green(void *user_data, track_t track_num) 
+_cdio_get_track_green(void *env, track_t track_num) 
 {
-  _img_private_t *_obj = user_data;
+  _img_private_t *_obj = env;
   
   if (!_obj->toc_init) _cdio_read_toc (_obj) ;
 
@@ -450,9 +451,9 @@ _cdio_get_track_green(void *user_data, track_t track_num)
   False is returned if there is no track entry.
 */
 static bool
-_cdio_get_track_msf(void *user_data, track_t track_num, msf_t *msf)
+_cdio_get_track_msf(void *env, track_t track_num, msf_t *msf)
 {
-  _img_private_t *_obj = user_data;
+  _img_private_t *_obj = env;
 
   if (NULL == msf) return false;
 
@@ -474,7 +475,7 @@ _cdio_get_track_msf(void *user_data, track_t track_num, msf_t *msf)
 #endif /* HAVE_FREEBSD_CDROM */
 
 /*!
-  Return a string containing the default VCD device if none is specified.
+  Return a string containing the default CD device if none is specified.
  */
 char *
 cdio_get_default_device_freebsd()
@@ -501,6 +502,7 @@ cdio_open_freebsd (const char *source_name)
     .get_arg            = _cdio_get_arg,
     .get_default_device = _cdio_get_default_device_freebsd,
     .get_first_track_num= _cdio_get_first_track_num,
+    .get_mcn            = NULL,
     .get_num_tracks     = _cdio_get_num_tracks,
     .get_track_format   = _cdio_get_track_format,
     .get_track_green    = _cdio_get_track_green,
@@ -508,7 +510,7 @@ cdio_open_freebsd (const char *source_name)
     .get_track_msf      = _cdio_get_track_msf,
     .lseek              = cdio_generic_lseek,
     .read               = cdio_generic_read,
-    .read_audio_sector  = _cdio_read_audio_sector,
+    .read_audio_sectors = _cdio_read_audio_sectors,
     .read_mode2_sector  = _cdio_read_mode2_sector,
     .read_mode2_sectors = _cdio_read_mode2_sectors,
     .set_arg            = _cdio_set_arg,
diff --git a/lib/_cdio_linux.c b/lib/_cdio_linux.c
index 489c7780..a814f050 100644
--- a/lib/_cdio_linux.c
+++ b/lib/_cdio_linux.c
@@ -1,5 +1,5 @@
 /*
-    $Id: _cdio_linux.c,v 1.21 2003/09/20 12:34:02 rocky Exp $
+    $Id: _cdio_linux.c,v 1.22 2003/09/25 09:38:16 rocky Exp $
 
     Copyright (C) 2001 Herbert Valerio Riedel <hvr@gnu.org>
     Copyright (C) 2002,2003 Rocky Bernstein <rocky@panix.com>
@@ -27,7 +27,7 @@
 # include "config.h"
 #endif
 
-static const char _rcsid[] = "$Id: _cdio_linux.c,v 1.21 2003/09/20 12:34:02 rocky Exp $";
+static const char _rcsid[] = "$Id: _cdio_linux.c,v 1.22 2003/09/25 09:38:16 rocky Exp $";
 
 #include <string.h>
 
@@ -267,10 +267,10 @@ _cdio_mmc_read_sectors (int fd, void *buf, lba_t lba, int sector_type,
    Can read only up to 25 blocks.
 */
 static int
-_cdio_read_audio_sectors (void *user_data, void *buf, lsn_t lsn, 
+_cdio_read_audio_sectors (void *env, void *buf, lsn_t lsn, 
 			  unsigned int nblocks)
 {
-  _img_private_t *_obj = user_data;
+  _img_private_t *_obj = env;
   return _cdio_mmc_read_sectors( _obj->gen.fd, buf, lsn, 
 				 CDIO_MMC_READ_TYPE_CDDA, nblocks);
 }
@@ -358,14 +358,14 @@ _read_packet_mode2_sectors (int fd, void *buf, lba_t lba,
    from lsn. Returns 0 if no error. 
  */
 static int
-_cdio_read_mode2_sector (void *user_data, void *data, lsn_t lsn, 
+_cdio_read_mode2_sector (void *env, void *data, lsn_t lsn, 
 			 bool mode2_form2)
 {
   char buf[M2RAW_SECTOR_SIZE] = { 0, };
   struct cdrom_msf *msf = (struct cdrom_msf *) &buf;
   msf_t _msf;
 
-  _img_private_t *_obj = user_data;
+  _img_private_t *_obj = env;
 
   cdio_lba_to_msf (cdio_lsn_to_lba(lsn), &_msf);
   msf->cdmsf_min0 = from_bcd8(_msf.m);
@@ -425,13 +425,13 @@ _cdio_read_mode2_sector (void *user_data, void *data, lsn_t lsn,
    from lsn. Returns 0 if no error. 
  */
 static int
-_cdio_read_audio_sector (void *user_data, void *data, lsn_t lsn)
+_cdio_read_audio_sector (void *env, void *data, lsn_t lsn)
 {
   char buf[CDIO_CD_FRAMESIZE_RAW] = { 0, };
   struct cdrom_msf *msf = (struct cdrom_msf *) &buf;
   msf_t _msf;
 
-  _img_private_t *_obj = user_data;
+  _img_private_t *_obj = env;
 
   cdio_lsn_to_msf (lsn, &_msf);
   msf->cdmsf_min0 = from_bcd8(_msf.m);
@@ -483,10 +483,10 @@ _cdio_read_audio_sector (void *user_data, void *data, lsn_t lsn)
    Returns 0 if no error. 
  */
 static int
-_cdio_read_mode2_sectors (void *user_data, void *data, lsn_t lsn, 
+_cdio_read_mode2_sectors (void *env, void *data, lsn_t lsn, 
 			  bool mode2_form2, unsigned int nblocks)
 {
-  _img_private_t *_obj = user_data;
+  _img_private_t *_obj = env;
   int i;
   int retval;
 
@@ -513,9 +513,9 @@ _cdio_read_mode2_sectors (void *user_data, void *data, lsn_t lsn,
    Return the size of the CD in logical block address (LBA) units.
  */
 static uint32_t 
-_cdio_stat_size (void *user_data)
+_cdio_stat_size (void *env)
 {
-  _img_private_t *_obj = user_data;
+  _img_private_t *_obj = env;
 
   struct cdrom_tocentry tocent;
   uint32_t size;
@@ -537,9 +537,9 @@ _cdio_stat_size (void *user_data)
   Set the key "arg" to "value" in source device.
 */
 static int
-_cdio_set_arg (void *user_data, const char key[], const char value[])
+_cdio_set_arg (void *env, const char key[], const char value[])
 {
-  _img_private_t *_obj = user_data;
+  _img_private_t *_obj = env;
 
   if (!strcmp (key, "source"))
     {
@@ -684,9 +684,9 @@ _cdio_eject_scsi(int fd)
   Return 0 if success and 1 for failure, and 2 if no routine.
  */
 static int 
-_cdio_eject_media (void *user_data) {
+_cdio_eject_media (void *env) {
 
-  _img_private_t *_obj = user_data;
+  _img_private_t *_obj = env;
   int ret=2;
   int status;
   int fd;
@@ -731,9 +731,9 @@ _cdio_eject_media (void *user_data) {
   Return the value associated with the key "arg".
 */
 static const char *
-_cdio_get_arg (void *user_data, const char key[])
+_cdio_get_arg (void *env, const char key[])
 {
-  _img_private_t *_obj = user_data;
+  _img_private_t *_obj = env;
 
   if (!strcmp (key, "source")) {
     return _obj->gen.source_name;
@@ -757,23 +757,40 @@ _cdio_get_arg (void *user_data, const char key[])
   CDIO_INVALID_TRACK is returned on error.
 */
 static track_t
-_cdio_get_first_track_num(void *user_data) 
+_cdio_get_first_track_num(void *env) 
 {
-  _img_private_t *_obj = user_data;
+  _img_private_t *_obj = env;
   
   if (!_obj->gen.toc_init) _cdio_read_toc (_obj) ;
 
   return FIRST_TRACK_NUM;
 }
 
+/*!
+  Return the media catalog number MCN.
+
+  Note: string is malloc'd so caller should free() then returned
+  string when done with it.
+
+ */
+static char *
+_cdio_get_mcn (void *env) {
+
+  struct cdrom_mcn mcn;
+  _img_private_t *_obj = env;
+  if (ioctl(_obj->gen.fd, CDROM_GET_MCN, &mcn) != 0)
+    return NULL;
+  return strdup(mcn.medium_catalog_number);
+}
+
 /*!
   Return the number of tracks in the current medium.
   CDIO_INVALID_TRACK is returned on error.
 */
 static track_t
-_cdio_get_num_tracks(void *user_data) 
+_cdio_get_num_tracks(void *env) 
 {
-  _img_private_t *_obj = user_data;
+  _img_private_t *_obj = env;
   
   if (!_obj->gen.toc_init) _cdio_read_toc (_obj) ;
 
@@ -784,9 +801,9 @@ _cdio_get_num_tracks(void *user_data)
   Get format of track. 
 */
 static track_format_t
-_cdio_get_track_format(void *user_data, track_t track_num) 
+_cdio_get_track_format(void *env, track_t track_num) 
 {
-  _img_private_t *_obj = user_data;
+  _img_private_t *_obj = env;
   
   if (!_obj->gen.toc_init) _cdio_read_toc (_obj) ;
 
@@ -817,9 +834,9 @@ _cdio_get_track_format(void *user_data, track_t track_num)
   FIXME: there's gotta be a better design for this and get_track_format?
 */
 static bool
-_cdio_get_track_green(void *user_data, track_t track_num) 
+_cdio_get_track_green(void *env, track_t track_num) 
 {
-  _img_private_t *_obj = user_data;
+  _img_private_t *_obj = env;
   
   if (!_obj->gen.toc_init) _cdio_read_toc (_obj) ;
 
@@ -842,9 +859,9 @@ _cdio_get_track_green(void *user_data, track_t track_num)
   False is returned if there is no track entry.
 */
 static bool
-_cdio_get_track_msf(void *user_data, track_t track_num, msf_t *msf)
+_cdio_get_track_msf(void *env, track_t track_num, msf_t *msf)
 {
-  _img_private_t *_obj = user_data;
+  _img_private_t *_obj = env;
 
   if (NULL == msf) return false;
 
@@ -945,6 +962,7 @@ cdio_open_linux (const char *orig_source_name)
     .get_arg            = _cdio_get_arg,
     .get_default_device = cdio_get_default_device_linux,
     .get_first_track_num= _cdio_get_first_track_num,
+    .get_mcn            = _cdio_get_mcn,
     .get_num_tracks     = _cdio_get_num_tracks,
     .get_track_format   = _cdio_get_track_format,
     .get_track_green    = _cdio_get_track_green,
diff --git a/lib/_cdio_nrg.c b/lib/_cdio_nrg.c
index c750dfa8..06c08a2e 100644
--- a/lib/_cdio_nrg.c
+++ b/lib/_cdio_nrg.c
@@ -1,5 +1,5 @@
 /*
-    $Id: _cdio_nrg.c,v 1.17 2003/09/20 12:34:02 rocky Exp $
+    $Id: _cdio_nrg.c,v 1.18 2003/09/25 09:38:16 rocky Exp $
 
     Copyright (C) 2001,2003 Herbert Valerio Riedel <hvr@gnu.org>
 
@@ -38,7 +38,7 @@
 #include "cdio_private.h"
 #include "_cdio_stdio.h"
 
-static const char _rcsid[] = "$Id: _cdio_nrg.c,v 1.17 2003/09/20 12:34:02 rocky Exp $";
+static const char _rcsid[] = "$Id: _cdio_nrg.c,v 1.18 2003/09/25 09:38:16 rocky Exp $";
 
 /* structures used */
 
@@ -143,7 +143,7 @@ typedef struct {
 } _img_private_t;
 
 static bool     _cdio_parse_nero_footer (_img_private_t *_obj);
-static uint32_t _cdio_stat_size (void *user_data);
+static uint32_t _cdio_stat_size (void *env);
 
 /* Updates internal track TOC, so we can later 
    simulate ioctl(CDROMREADTOCENTRY).
@@ -517,9 +517,9 @@ _cdio_init (_img_private_t *_obj)
   information in each sector.
 */
 static off_t
-_cdio_lseek (void *user_data, off_t offset, int whence)
+_cdio_lseek (void *env, off_t offset, int whence)
 {
-  _img_private_t *_obj = user_data;
+  _img_private_t *_obj = env;
 
   /* real_offset is the real byte offset inside the disk image
      The number below was determined empirically. I'm guessing
@@ -576,16 +576,16 @@ _cdio_lseek (void *user_data, off_t offset, int whence)
    boundaries.
 */
 static ssize_t
-_cdio_read (void *user_data, void *buf, size_t size)
+_cdio_read (void *env, void *buf, size_t size)
 {
-  _img_private_t *_obj = user_data;
+  _img_private_t *_obj = env;
   return cdio_stream_read(_obj->gen.data_source, buf, size, 1);
 }
 
 static uint32_t 
-_cdio_stat_size (void *user_data)
+_cdio_stat_size (void *env)
 {
-  _img_private_t *_obj = user_data;
+  _img_private_t *_obj = env;
 
   return _obj->size;
 }
@@ -595,10 +595,10 @@ _cdio_stat_size (void *user_data)
    from LSN. Returns 0 if no error. 
  */
 static int
-_cdio_read_audio_sectors (void *user_data, void *data, lsn_t lsn, 
+_cdio_read_audio_sectors (void *env, void *data, lsn_t lsn, 
 			  unsigned int nblocks)
 {
-  _img_private_t *_obj = user_data;
+  _img_private_t *_obj = env;
 
   CdioListNode *node;
 
@@ -635,10 +635,10 @@ _cdio_read_audio_sectors (void *user_data, void *data, lsn_t lsn,
 }
 
 static int
-_cdio_read_mode2_sector (void *user_data, void *data, lsn_t lsn, 
+_cdio_read_mode2_sector (void *env, void *data, lsn_t lsn, 
 			 bool mode2_form2)
 {
-  _img_private_t *_obj = user_data;
+  _img_private_t *_obj = env;
   char buf[CDIO_CD_FRAMESIZE_RAW] = { 0, };
   int blocksize = _obj->sector_2336 
     ? M2RAW_SECTOR_SIZE : CDIO_CD_FRAMESIZE_RAW;
@@ -691,10 +691,10 @@ _cdio_read_mode2_sector (void *user_data, void *data, lsn_t lsn,
    Returns 0 if no error. 
  */
 static int
-_cdio_read_mode2_sectors (void *user_data, void *data, uint32_t lsn, 
+_cdio_read_mode2_sectors (void *env, void *data, uint32_t lsn, 
 		     bool mode2_form2, unsigned nblocks)
 {
-  _img_private_t *_obj = user_data;
+  _img_private_t *_obj = env;
   int i;
   int retval;
 
@@ -720,9 +720,9 @@ _cdio_read_mode2_sectors (void *user_data, void *data, uint32_t lsn,
   Set the device to use in I/O operations.
 */
 static int
-_cdio_set_arg (void *user_data, const char key[], const char value[])
+_cdio_set_arg (void *env, const char key[], const char value[])
 {
-  _img_private_t *_obj = user_data;
+  _img_private_t *_obj = env;
 
   if (!strcmp (key, "source"))
     {
@@ -743,9 +743,9 @@ _cdio_set_arg (void *user_data, const char key[], const char value[])
   Return the value associated with the key "arg".
 */
 static const char *
-_cdio_get_arg (void *user_data, const char key[])
+_cdio_get_arg (void *env, const char key[])
 {
-  _img_private_t *_obj = user_data;
+  _img_private_t *_obj = env;
 
   if (!strcmp (key, "source")) {
     return _obj->gen.source_name;
@@ -767,9 +767,9 @@ cdio_get_default_device_nrg()
   CDIO_INVALID_TRACK is returned on error.
 */
 static track_t
-_cdio_get_first_track_num(void *user_data) 
+_cdio_get_first_track_num(void *env) 
 {
-  _img_private_t *_obj = user_data;
+  _img_private_t *_obj = env;
   
   return _obj->first_track_num;
 }
@@ -779,9 +779,9 @@ _cdio_get_first_track_num(void *user_data)
   one big track. 
 */
 static track_t
-_cdio_get_num_tracks(void *user_data) 
+_cdio_get_num_tracks(void *env) 
 {
-  _img_private_t *_obj = user_data;
+  _img_private_t *_obj = env;
 
   return _obj->total_tracks;
 }
@@ -791,9 +791,9 @@ _cdio_get_num_tracks(void *user_data)
   CDIO_INVALID_TRACK is returned on error.
 */
 static track_format_t
-_cdio_get_track_format(void *user_data, track_t track_num) 
+_cdio_get_track_format(void *env, track_t track_num) 
 {
-  _img_private_t *_obj = user_data;
+  _img_private_t *_obj = env;
   
   if (track_num > _obj->total_tracks || track_num == 0) 
     return TRACK_FORMAT_ERROR;
@@ -810,9 +810,9 @@ _cdio_get_track_format(void *user_data, track_t track_num)
   FIXME: there's gotta be a better design for this and get_track_format?
 */
 static bool
-_cdio_get_track_green(void *user_data, track_t track_num) 
+_cdio_get_track_green(void *env, track_t track_num) 
 {
-  _img_private_t *_obj = user_data;
+  _img_private_t *_obj = env;
   
   if (track_num > _obj->total_tracks || track_num == 0) 
     return false;
@@ -827,9 +827,9 @@ _cdio_get_track_green(void *user_data, track_t track_num)
   using track_num LEADOUT_TRACK or the total tracks+1.
 */
 static bool
-_cdio_get_track_msf(void *user_data, track_t track_num, msf_t *msf)
+_cdio_get_track_msf(void *env, track_t track_num, msf_t *msf)
 {
-  _img_private_t *_obj = user_data;
+  _img_private_t *_obj = env;
 
   if (NULL == msf) return 1;
 
diff --git a/lib/_cdio_osx.c b/lib/_cdio_osx.c
index 3f0a82f4..f20218ba 100644
--- a/lib/_cdio_osx.c
+++ b/lib/_cdio_osx.c
@@ -1,5 +1,5 @@
 /*
-    $Id: _cdio_osx.c,v 1.7 2003/09/20 12:34:02 rocky Exp $
+    $Id: _cdio_osx.c,v 1.8 2003/09/25 09:38:16 rocky Exp $
 
     Copyright (C) 2003 Rocky Bernstein <rocky@panix.com> from vcdimager code
     Copyright (C) 2001 Herbert Valerio Riedel <hvr@gnu.org>
@@ -31,7 +31,7 @@
 # include "config.h"
 #endif
 
-static const char _rcsid[] = "$Id: _cdio_osx.c,v 1.7 2003/09/20 12:34:02 rocky Exp $";
+static const char _rcsid[] = "$Id: _cdio_osx.c,v 1.8 2003/09/25 09:38:16 rocky Exp $";
 
 #include <cdio/sector.h>
 #include <cdio/util.h>
@@ -83,8 +83,8 @@ typedef struct {
 } _img_private_t;
 
 static void 
-_cdio_osx_free (void *user_data) {
-  _img_private_t *_obj = user_data;
+_cdio_osx_free (void *env) {
+  _img_private_t *_obj = env;
   if (NULL == _obj) return;
   cdio_generic_free(_obj);
   if (NULL != _obj->pp_lba) free((void *) _obj->pp_lba);
@@ -155,10 +155,10 @@ _cdio_read_mode2_form2_sectors (int device_handle, void *data, lsn_t lsn,
    Returns 0 if no error. 
  */
 static int
-_cdio_read_mode2_sectors (void *user_data, void *data, lsn_t lsn, 
+_cdio_read_mode2_sectors (void *env, void *data, lsn_t lsn, 
 			  bool mode2_form2, unsigned int nblocks)
 {
-  _img_private_t *_obj = user_data;
+  _img_private_t *_obj = env;
   int i;
   int retval;
 
@@ -184,10 +184,10 @@ _cdio_read_mode2_sectors (void *user_data, void *data, lsn_t lsn,
    Returns 0 if no error. 
  */
 static int
-_cdio_read_audio_sectors (void *user_data, void *data, lsn_t lsn, 
+_cdio_read_audio_sectors (void *env, void *data, lsn_t lsn, 
 			  unsigned int nblocks)
 {
-  return _cdio_read_mode2_sectors(user_data, data, lsn, true, nblocks);
+  return _cdio_read_mode2_sectors(env, data, lsn, true, nblocks);
 }
 
 /*!
@@ -195,19 +195,19 @@ _cdio_read_audio_sectors (void *user_data, void *data, lsn_t lsn,
    from lsn. Returns 0 if no error. 
  */
 static int
-_cdio_read_mode2_sector (void *user_data, void *data, lsn_t lsn, 
+_cdio_read_mode2_sector (void *env, void *data, lsn_t lsn, 
 			 bool mode2_form2)
 {
-  return _cdio_read_mode2_sectors(user_data, data, lsn, mode2_form2, 1);
+  return _cdio_read_mode2_sectors(env, data, lsn, mode2_form2, 1);
 }
 
 /*!
   Set the key "arg" to "value" in source device.
 */
 static int
-_cdio_set_arg (void *user_data, const char key[], const char value[])
+_cdio_set_arg (void *env, const char key[], const char value[])
 {
-  _img_private_t *_obj = user_data;
+  _img_private_t *_obj = env;
 
   if (!strcmp (key, "source"))
     {
@@ -406,9 +406,9 @@ _cdio_read_toc (_img_private_t *_obj)
   False is returned if there is no track entry.
 */
 static lsn_t
-_cdio_get_track_lba(void *user_data, track_t track_num)
+_cdio_get_track_lba(void *env, track_t track_num)
 {
-  _img_private_t *_obj = user_data;
+  _img_private_t *_obj = env;
 
   if (!_obj->toc_init) _cdio_read_toc (_obj) ;
 
@@ -432,9 +432,9 @@ _cdio_get_track_lba(void *user_data, track_t track_num)
  */
 
 static int 
-_cdio_eject_media (void *user_data) {
+_cdio_eject_media (void *env) {
 
-  _img_private_t *_obj = user_data;
+  _img_private_t *_obj = env;
 
   FILE *p_eject;
   char *psz_disk;
@@ -476,18 +476,18 @@ _cdio_eject_media (void *user_data) {
    Return the size of the CD in logical block address (LBA) units.
  */
 static uint32_t 
-_cdio_stat_size (void *user_data)
+_cdio_stat_size (void *env)
 {
-  return _cdio_get_track_lba(user_data, CDIO_CDROM_LEADOUT_TRACK);
+  return _cdio_get_track_lba(env, CDIO_CDROM_LEADOUT_TRACK);
 }
 
 /*!
   Return the value associated with the key "arg".
 */
 static const char *
-_cdio_get_arg (void *user_data, const char key[])
+_cdio_get_arg (void *env, const char key[])
 {
-  _img_private_t *_obj = user_data;
+  _img_private_t *_obj = env;
 
   if (!strcmp (key, "source")) {
     return _obj->gen.source_name;
@@ -507,9 +507,9 @@ _cdio_get_arg (void *user_data, const char key[])
   CDIO_INVALID_TRACK is returned on error.
 */
 static track_t
-_cdio_get_first_track_num(void *user_data) 
+_cdio_get_first_track_num(void *env) 
 {
-  _img_private_t *_obj = user_data;
+  _img_private_t *_obj = env;
   
   if (!_obj->toc_init) _cdio_read_toc (_obj) ;
   
@@ -539,9 +539,9 @@ _cdio_get_first_track_num(void *user_data)
   This is the externally called interface.
 */
 static track_t
-_cdio_get_num_tracks(void *user_data) 
+_cdio_get_num_tracks(void *env) 
 {
-  _img_private_t *_obj = user_data;
+  _img_private_t *_obj = env;
   
   if (!_obj->toc_init) _cdio_read_toc (_obj) ;
   return( _obj->num_tracks );
@@ -551,9 +551,9 @@ _cdio_get_num_tracks(void *user_data)
   Get format of track. 
 */
 static track_format_t
-_cdio_get_track_format(void *user_data, track_t track_num) 
+_cdio_get_track_format(void *env, track_t track_num) 
 {
-  _img_private_t *_obj = user_data;
+  _img_private_t *_obj = env;
   
   if (!_obj->toc_init) _cdio_read_toc (_obj) ;
 
@@ -586,7 +586,7 @@ _cdio_get_track_format(void *user_data, track_t track_num)
   FIXME: there's gotta be a better design for this and get_track_format?
 */
 static bool
-_cdio_get_track_green(void *user_data, track_t track_num) 
+_cdio_get_track_green(void *env, track_t track_num) 
 {
 
 #if 0  
@@ -637,6 +637,7 @@ cdio_open_osx (const char *source_name)
     .get_arg            = _cdio_get_arg,
     .get_default_device = cdio_get_default_device_osx,
     .get_first_track_num= _cdio_get_first_track_num,
+    .get_mcn            = NULL, /*there is a readMCN, but how to use? */
     .get_num_tracks     = _cdio_get_num_tracks,
     .get_track_format   = _cdio_get_track_format,
     .get_track_green    = _cdio_get_track_green,
diff --git a/lib/_cdio_win32.c b/lib/_cdio_win32.c
index 8b4ad1c2..be6c6bb0 100644
--- a/lib/_cdio_win32.c
+++ b/lib/_cdio_win32.c
@@ -1,5 +1,5 @@
 /*
-    $Id: _cdio_win32.c,v 1.13 2003/09/21 06:10:59 rocky Exp $
+    $Id: _cdio_win32.c,v 1.14 2003/09/25 09:38:16 rocky Exp $
 
     Copyright (C) 2003 Rocky Bernstein <rocky@panix.com>
 
@@ -26,7 +26,7 @@
 # include "config.h"
 #endif
 
-static const char _rcsid[] = "$Id: _cdio_win32.c,v 1.13 2003/09/21 06:10:59 rocky Exp $";
+static const char _rcsid[] = "$Id: _cdio_win32.c,v 1.14 2003/09/25 09:38:16 rocky Exp $";
 
 #include <cdio/cdio.h>
 #include <cdio/sector.h>
@@ -1076,6 +1076,7 @@ cdio_open_win32 (const char *source_name)
     .get_arg            = _cdio_get_arg,
     .get_default_device = cdio_get_default_device_win32,
     .get_first_track_num= _cdio_get_first_track_num,
+    .get_mcn            = NULL, 
     .get_num_tracks     = _cdio_get_num_tracks,
     .get_track_format   = _cdio_get_track_format,
     .get_track_green    = _cdio_get_track_green,
diff --git a/lib/cdio.c b/lib/cdio.c
index 94ffd309..c8ddb4b5 100644
--- a/lib/cdio.c
+++ b/lib/cdio.c
@@ -1,5 +1,5 @@
 /*
-    $Id: cdio.c,v 1.26 2003/09/20 12:34:02 rocky Exp $
+    $Id: cdio.c,v 1.27 2003/09/25 09:38:16 rocky Exp $
 
     Copyright (C) 2003 Rocky Bernstein <rocky@panix.com>
     Copyright (C) 2001 Herbert Valerio Riedel <hvr@gnu.org>
@@ -35,7 +35,7 @@
 #include <cdio/logging.h>
 #include "cdio_private.h"
 
-static const char _rcsid[] = "$Id: cdio.c,v 1.26 2003/09/20 12:34:02 rocky Exp $";
+static const char _rcsid[] = "$Id: cdio.c,v 1.27 2003/09/25 09:38:16 rocky Exp $";
 
 
 const char *track_format2str[6] = 
@@ -171,7 +171,7 @@ cdio_eject_media (CdIo **obj)
   if ((obj == NULL) || (*obj == NULL)) return 1;
 
   if ((*obj)->op.eject_media) {
-    int ret = (*obj)->op.eject_media ((*obj)->user_data);
+    int ret = (*obj)->op.eject_media ((*obj)->env);
     if (0 == ret) {
       cdio_destroy(*obj);
       *obj = NULL;
@@ -194,7 +194,7 @@ cdio_get_arg (const CdIo *obj, const char key[])
   if (obj == NULL) return NULL;
   
   if (obj->op.get_arg) {
-    return obj->op.get_arg (obj->user_data, key);
+    return obj->op.get_arg (obj->env, key);
   } else {
     return NULL;
   }
@@ -257,12 +257,27 @@ cdio_get_first_track_num (const CdIo *obj)
   cdio_assert (obj != NULL);
 
   if (obj->op.get_first_track_num) {
-    return obj->op.get_first_track_num (obj->user_data);
+    return obj->op.get_first_track_num (obj->env);
   } else {
     return CDIO_INVALID_TRACK;
   }
 }
 
+/*!
+  Return a string containing the name of the driver in use.
+  if CdIo is NULL (we haven't initialized a specific device driver), 
+  then return NULL.
+*/
+char *
+cdio_get_mcn (const CdIo *obj) 
+{
+  if (obj->op.get_mcn) {
+    return obj->op.get_mcn (obj->env);
+  } else {
+    return NULL;
+  }
+}
+
 /*! 
   Return the number of tracks in the current medium.
   CDIO_INVALID_TRACK is returned on error.
@@ -273,7 +288,7 @@ cdio_get_num_tracks (const CdIo *obj)
   if (obj == NULL) return CDIO_INVALID_TRACK;
 
   if (obj->op.get_num_tracks) {
-    return obj->op.get_num_tracks (obj->user_data);
+    return obj->op.get_num_tracks (obj->env);
   } else {
     return CDIO_INVALID_TRACK;
   }
@@ -288,7 +303,7 @@ cdio_get_track_format(const CdIo *obj, track_t track_num)
   cdio_assert (obj != NULL);
 
   if (obj->op.get_track_format) {
-    return obj->op.get_track_format (obj->user_data, track_num);
+    return obj->op.get_track_format (obj->env, track_num);
   } else {
     return TRACK_FORMAT_ERROR;
   }
@@ -308,7 +323,7 @@ cdio_get_track_green(const CdIo *obj, track_t track_num)
   cdio_assert (obj != NULL);
 
   if (obj->op.get_track_green) {
-    return obj->op.get_track_green (obj->user_data, track_num);
+    return obj->op.get_track_green (obj->env, track_num);
   } else {
     return false;
   }
@@ -327,7 +342,7 @@ cdio_get_track_lba(const CdIo *obj, track_t track_num)
   if (obj == NULL) return CDIO_INVALID_LBA;
 
   if (obj->op.get_track_lba) {
-    return obj->op.get_track_lba (obj->user_data, track_num);
+    return obj->op.get_track_lba (obj->env, track_num);
   } else {
     msf_t msf;
     if (obj->op.get_track_msf) 
@@ -350,7 +365,7 @@ cdio_get_track_lsn(const CdIo *obj, track_t track_num)
   if (obj == NULL) return CDIO_INVALID_LBA;
 
   if (obj->op.get_track_lba) {
-    return cdio_lba_to_lsn(obj->op.get_track_lba (obj->user_data, track_num));
+    return cdio_lba_to_lsn(obj->op.get_track_lba (obj->env, track_num));
   } else {
     msf_t msf;
     if (cdio_get_track_msf(obj, track_num, &msf))
@@ -372,9 +387,9 @@ cdio_get_track_msf(const CdIo *obj, track_t track_num, /*out*/ msf_t *msf)
   cdio_assert (obj != NULL);
 
   if (obj->op.get_track_msf) {
-    return obj->op.get_track_msf (obj->user_data, track_num, msf);
+    return obj->op.get_track_msf (obj->env, track_num, msf);
   } else if (obj->op.get_track_lba) {
-    lba_t lba = obj->op.get_track_lba (obj->user_data, track_num);
+    lba_t lba = obj->op.get_track_lba (obj->env, track_num);
     if (lba  == CDIO_INVALID_LBA) return false;
     cdio_lba_to_msf(lba, msf);
     return true;
@@ -443,13 +458,13 @@ cdio_init(void)
 }
 
 CdIo *
-cdio_new (void *user_data, const cdio_funcs *funcs)
+cdio_new (void *env, const cdio_funcs *funcs)
 {
   CdIo *new_obj;
 
   new_obj = _cdio_malloc (sizeof (CdIo));
 
-  new_obj->user_data = user_data;
+  new_obj->env = env;
   new_obj->op = *funcs;
 
   return new_obj;
@@ -465,7 +480,7 @@ cdio_destroy (CdIo *obj)
   if (obj == NULL) return;
 
   if (obj->op.free != NULL) 
-    obj->op.free (obj->user_data);
+    obj->op.free (obj->env);
   free (obj);
 }
 
@@ -480,7 +495,7 @@ cdio_lseek (const CdIo *obj, off_t offset, int whence)
   if (obj == NULL) return -1;
   
   if (obj->op.lseek)
-    return obj->op.lseek (obj->user_data, offset, whence);
+    return obj->op.lseek (obj->env, offset, whence);
   return -1;
 }
 
@@ -495,7 +510,7 @@ cdio_read (const CdIo *obj, void *buf, size_t size)
   if (obj == NULL) return -1;
   
   if (obj->op.read)
-    return obj->op.read (obj->user_data, buf, size);
+    return obj->op.read (obj->env, buf, size);
   return -1;
 }
 
@@ -506,7 +521,7 @@ cdio_read_audio_sector (const CdIo *obj, void *buf, lsn_t lsn)
   cdio_assert (buf != NULL);
 
   if  (obj->op.read_audio_sectors != NULL)
-    return obj->op.read_audio_sectors (obj->user_data, buf, lsn, 1);
+    return obj->op.read_audio_sectors (obj->env, buf, lsn, 1);
   return -1;
 }
 
@@ -518,7 +533,7 @@ cdio_read_audio_sectors (const CdIo *obj, void *buf, lsn_t lsn,
   cdio_assert (buf != NULL);
 
   if  (obj->op.read_audio_sectors != NULL)
-    return obj->op.read_audio_sectors (obj->user_data, buf, lsn, nblocks);
+    return obj->op.read_audio_sectors (obj->env, buf, lsn, nblocks);
   return -1;
 }
 
@@ -585,7 +600,7 @@ cdio_read_mode2_sector (const CdIo *obj, void *buf, lsn_t lsn,
 	      || obj->op.read_mode2_sectors != NULL);
 
   if (obj->op.read_mode2_sector)
-    return obj->op.read_mode2_sector (obj->user_data, buf, lsn, is_form2);
+    return obj->op.read_mode2_sector (obj->env, buf, lsn, is_form2);
 
   /* fallback */
   if (obj->op.read_mode2_sectors != NULL)
@@ -601,7 +616,7 @@ cdio_read_mode2_sectors (const CdIo *obj, void *buf, lsn_t lsn, bool mode2raw,
   cdio_assert (buf != NULL);
   cdio_assert (obj->op.read_mode2_sectors != NULL);
   
-  return obj->op.read_mode2_sectors (obj->user_data, buf, lsn,
+  return obj->op.read_mode2_sectors (obj->env, buf, lsn,
                                      mode2raw, num_sectors);
 }
 
@@ -610,7 +625,7 @@ cdio_stat_size (const CdIo *obj)
 {
   cdio_assert (obj != NULL);
 
-  return obj->op.stat_size (obj->user_data);
+  return obj->op.stat_size (obj->env);
 }
 
 /*!
@@ -623,7 +638,7 @@ cdio_set_arg (CdIo *obj, const char key[], const char value[])
   cdio_assert (obj->op.set_arg != NULL);
   cdio_assert (key != NULL);
 
-  return obj->op.set_arg (obj->user_data, key, value);
+  return obj->op.set_arg (obj->env, key, value);
 }
 
 static CdIo *
diff --git a/lib/cdio_private.h b/lib/cdio_private.h
index 2a79d5fc..9dec75f5 100644
--- a/lib/cdio_private.h
+++ b/lib/cdio_private.h
@@ -1,5 +1,5 @@
 /*
-    $Id: cdio_private.h,v 1.13 2003/09/20 12:34:02 rocky Exp $
+    $Id: cdio_private.h,v 1.14 2003/09/25 09:38:16 rocky Exp $
 
     Copyright (C) 2003 Rocky Bernstein <rocky@panix.com>
 
@@ -43,34 +43,40 @@ extern "C" {
       Eject media in CD drive. If successful, as a side effect we 
       also free obj. Return 0 if success and 1 for failure.
     */
-    int (*eject_media) (void *user_data);
+    int (*eject_media) (void *env);
     
     /*!
       Release and free resources associated with cd. 
     */
-    void (*free) (void *user_data);
+    void (*free) (void *env);
     
     /*!
       Return the value associated with the key "arg".
     */
-    const char * (*get_arg) (void *user_data, const char key[]);
+    const char * (*get_arg) (void *env, const char key[]);
     
     /*!
       Return a string containing the default CD device if none is specified.
     */
     char * (*get_default_device)(void);
     
+    /*!  
+      Return the media catalog number MCN from the CD or NULL if
+      there is none or we don't have the ability to get it.
+    */
+    char * (*get_mcn) (void *env);
+
     /*!
       Return the number of of the first track. 
       CDIO_INVALID_TRACK is returned on error.
     */
-    track_t (*get_first_track_num) (void *user_data);
+    track_t (*get_first_track_num) (void *env);
     
     /*! 
       Return the number of tracks in the current medium.
       CDIO_INVALID_TRACK is returned on error.
     */
-    track_t (*get_num_tracks) (void *user_data);
+    track_t (*get_num_tracks) (void *env);
     
     /*!  
       Return the starting LBA for track number
@@ -79,12 +85,12 @@ extern "C" {
       using track_num LEADOUT_TRACK or the total tracks+1.
       CDIO_INVALID_LBA is returned on error.
     */
-    lba_t (*get_track_lba) (void *user_data, track_t track_num);
+    lba_t (*get_track_lba) (void *env, track_t track_num);
     
     /*!  
       Get format of track. 
     */
-    track_format_t (*get_track_format) (void *user_data, track_t track_num);
+    track_format_t (*get_track_format) (void *env, track_t track_num);
     
     /*!
       Return true if we have XA data (green, mode2 form1) or
@@ -94,7 +100,7 @@ extern "C" {
       
       FIXME: there's gotta be a better design for this and get_track_format?
     */
-    bool (*get_track_green) (void *user_data, track_t track_num);
+    bool (*get_track_green) (void *env, track_t track_num);
     
     /*!  
       Return the starting MSF (minutes/secs/frames) for track number
@@ -103,34 +109,34 @@ extern "C" {
       using track_num LEADOUT_TRACK or the total tracks+1.
       False is returned on error.
     */
-    bool (*get_track_msf) (void *user_data, track_t track_num, msf_t *msf);
+    bool (*get_track_msf) (void *env, track_t track_num, msf_t *msf);
     
     /*!
       lseek - reposition read/write file offset
       Returns (off_t) -1 on error. 
       Similar to libc's lseek()
     */
-    off_t (*lseek) (void *user_data, off_t offset, int whence);
+    off_t (*lseek) (void *env, off_t offset, int whence);
     
     /*!
       Reads into buf the next size bytes.
       Returns -1 on error. 
       Similar to libc's read()
     */
-    ssize_t (*read) (void *user_data, void *buf, size_t size);
+    ssize_t (*read) (void *env, void *buf, size_t size);
     
     /*!
       Reads a single mode2 sector from cd device into buf starting
       from lsn. Returns 0 if no error. 
     */
-    int (*read_audio_sectors) (void *user_data, void *buf, lsn_t lsn,
+    int (*read_audio_sectors) (void *env, void *buf, lsn_t lsn,
 			       unsigned int nblocks);
     
     /*!
       Reads a single mode2 sector from cd device into buf starting
       from lsn. Returns 0 if no error. 
     */
-    int (*read_mode2_sector) (void *user_data, void *buf, lsn_t lsn, 
+    int (*read_mode2_sector) (void *env, void *buf, lsn_t lsn, 
 			      bool mode2raw);
     
     /*!
@@ -138,18 +144,18 @@ extern "C" {
       from lsn.
       Returns 0 if no error. 
     */
-    int (*read_mode2_sectors) (void *user_data, void *buf, lsn_t lsn, 
+    int (*read_mode2_sectors) (void *env, void *buf, lsn_t lsn, 
 			       bool mode2raw, unsigned int nblocks);
     
     /*!
       Set the arg "key" with "value" in the source device.
     */
-    int (*set_arg) (void *user_data, const char key[], const char value[]);
+    int (*set_arg) (void *env, const char key[], const char value[]);
     
     /*!
       Return the size of the CD in logical block address (LBA) units.
     */
-    uint32_t (*stat_size) (void *user_data);
+    uint32_t (*stat_size) (void *env);
     
   } cdio_funcs;
 
@@ -158,7 +164,7 @@ extern "C" {
   struct _CdIo {
     driver_id_t driver_id; /* Particular driver opened. */
     cdio_funcs op;         /* driver-specific routines handling implimentatin*/
-    void *user_data;       /* environment. Passed to routine above. */
+    void *env;       /* environment. Passed to routine above. */
   };
 
   /*!
@@ -191,7 +197,7 @@ extern "C" {
     lba_t   lba;              /* Current LBA */
   } internal_position_t;
   
-  CdIo * cdio_new (void *user_data, const cdio_funcs *funcs);
+  CdIo * cdio_new (void *env, const cdio_funcs *funcs);
 
   /* The below structure describes a specific CD Input driver  */
   typedef struct 
@@ -225,36 +231,36 @@ extern "C" {
     Bogus eject media when there is no ejectable media, e.g. a disk image
     We always return 2. Should we also free resources? 
   */
-  int cdio_generic_bogus_eject_media (void *user_data);
+  int cdio_generic_bogus_eject_media (void *env);
 
   /*!
     Release and free resources associated with cd. 
   */
-  void cdio_generic_free (void *user_data);
+  void cdio_generic_free (void *env);
 
   /*!
     Initialize CD device.
   */
-  bool cdio_generic_init (void *user_data);
+  bool cdio_generic_init (void *env);
 
   /*!
     Reads into buf the next size bytes.
     Returns -1 on error. 
     Is in fact libc's read().
   */
-  off_t cdio_generic_lseek (void *user_data, off_t offset, int whence);
+  off_t cdio_generic_lseek (void *env, off_t offset, int whence);
 
   /*!
     Reads into buf the next size bytes.
     Returns -1 on error. 
     Is in fact libc's read().
   */
-  ssize_t cdio_generic_read (void *user_data, void *buf, size_t size);
+  ssize_t cdio_generic_read (void *env, void *buf, size_t size);
 
   /*!
     Release and free resources associated with stream or disk image.
   */
-  void cdio_generic_stream_free (void *user_data);
+  void cdio_generic_stream_free (void *env);
 
   /*!  
     Return true if source_name could be a device containing a CD-ROM on
diff --git a/src/cd-info.c b/src/cd-info.c
index cd0fb160..0fc8dd48 100644
--- a/src/cd-info.c
+++ b/src/cd-info.c
@@ -1,5 +1,5 @@
 /*
-    $Id: cd-info.c,v 1.37 2003/09/21 04:36:41 rocky Exp $
+    $Id: cd-info.c,v 1.38 2003/09/25 09:38:16 rocky Exp $
 
     Copyright (C) 2003 Rocky Bernstein <rocky@panix.com>
     Copyright (C) 1996,1997,1998  Gerd Knorr <kraxel@bytesex.org>
@@ -66,7 +66,6 @@
 #endif
 
 #if CDIO_IOCTL_FINISHED
-struct cdrom_mcn           mcn;
 struct cdrom_multisession  ms;
 struct cdrom_subchnl       sub;
 #endif
@@ -736,6 +735,7 @@ main(int argc, const char *argv[])
   int            first_data  = -1;  /* # of first data track */
   int            first_audio = -1;  /* # of first audio track */
   cdio_analysis_t cdio_analysis; 
+  char           *media_catalog_number;  
       
   memset(&cdio_analysis, 0, sizeof(cdio_analysis));
   init();
@@ -845,19 +845,21 @@ main(int argc, const char *argv[])
     if (i == num_tracks) i = CDIO_CDROM_LEADOUT_TRACK-1;
   }
 
+  /* get MCN */
+  media_catalog_number = cdio_get_mcn(cdio);
+  printf("Get MCN     : "); fflush(stdout);
+  if (NULL == media_catalog_number)
+    printf("not available\n");
+  else {
+    printf("%s\n", media_catalog_number);
+    free(media_catalog_number);
+  }
+  
+    
 #if CDIO_IOCTL_FINISHED
   if (!opts.no_ioctl) {
     printf(STRONG "What ioctl's report...\n" NORMAL);
   
-#ifdef CDROM_GET_MCN
-    /* get mcn */
-    printf("Get MCN     : "); fflush(stdout);
-    if (ioctl(filehandle,CDROM_GET_MCN, &mcn))
-      printf("FAILED\n");
-    else
-      printf("%s\n",mcn.medium_catalog_number);
-#endif
-    
 #ifdef CDROM_DISC_STATUS
     /* get disk status */
     printf("disc status : "); fflush(stdout);
diff --git a/test/cdda.right b/test/cdda.right
index cef76802..0d2f841d 100644
--- a/test/cdda.right
+++ b/test/cdda.right
@@ -6,6 +6,7 @@ CD-ROM Track List (1 - 1)
   #: MSF       LSN     Type
   1: 00:02:00  000000  audio
 170: 00:06:02  000302  leadout
+Get MCN     : not available
 __________________________________
 CD Analysis Report
 Audio CD, CDDB disc ID is 02000401
diff --git a/test/check_opts0.right b/test/check_opts0.right
index 29fd7390..05faba49 100644
--- a/test/check_opts0.right
+++ b/test/check_opts0.right
@@ -1,6 +1,7 @@
 This is free software; see the source for copying conditions.
 There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A
 PARTICULAR PURPOSE.
+Get MCN     : not available
 __________________________________
 CD Analysis Report
 CD-ROM with ISO 9660 filesystem
diff --git a/test/check_opts1.right b/test/check_opts1.right
index 29fd7390..05faba49 100644
--- a/test/check_opts1.right
+++ b/test/check_opts1.right
@@ -1,6 +1,7 @@
 This is free software; see the source for copying conditions.
 There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A
 PARTICULAR PURPOSE.
+Get MCN     : not available
 __________________________________
 CD Analysis Report
 CD-ROM with ISO 9660 filesystem
diff --git a/test/check_opts2.right b/test/check_opts2.right
index 8a94dfef..c9a3ddc7 100644
--- a/test/check_opts2.right
+++ b/test/check_opts2.right
@@ -6,3 +6,4 @@ CD-ROM Track List (1 - 1)
   #: MSF       LSN     Type
   1: 00:02:00  000000  data
 170: 00:06:02  000302  leadout
+Get MCN     : not available
diff --git a/test/check_opts3.right b/test/check_opts3.right
index 8a94dfef..c9a3ddc7 100644
--- a/test/check_opts3.right
+++ b/test/check_opts3.right
@@ -6,3 +6,4 @@ CD-ROM Track List (1 - 1)
   #: MSF       LSN     Type
   1: 00:02:00  000000  data
 170: 00:06:02  000302  leadout
+Get MCN     : not available
diff --git a/test/check_opts4.right b/test/check_opts4.right
index 331f2135..54d2e136 100644
--- a/test/check_opts4.right
+++ b/test/check_opts4.right
@@ -6,6 +6,7 @@ CD-ROM Track List (1 - 1)
   #: MSF       LSN     Type
   1: 00:02:00  000000  data
 170: 00:06:02  000302  leadout
+Get MCN     : not available
 __________________________________
 CD Analysis Report
 CD-ROM with ISO 9660 filesystem
diff --git a/test/check_opts5.right b/test/check_opts5.right
index 331f2135..54d2e136 100644
--- a/test/check_opts5.right
+++ b/test/check_opts5.right
@@ -6,6 +6,7 @@ CD-ROM Track List (1 - 1)
   #: MSF       LSN     Type
   1: 00:02:00  000000  data
 170: 00:06:02  000302  leadout
+Get MCN     : not available
 __________________________________
 CD Analysis Report
 CD-ROM with ISO 9660 filesystem
diff --git a/test/check_opts6.right b/test/check_opts6.right
index 331f2135..54d2e136 100644
--- a/test/check_opts6.right
+++ b/test/check_opts6.right
@@ -6,6 +6,7 @@ CD-ROM Track List (1 - 1)
   #: MSF       LSN     Type
   1: 00:02:00  000000  data
 170: 00:06:02  000302  leadout
+Get MCN     : not available
 __________________________________
 CD Analysis Report
 CD-ROM with ISO 9660 filesystem
diff --git a/test/check_opts7.right b/test/check_opts7.right
index 331f2135..54d2e136 100644
--- a/test/check_opts7.right
+++ b/test/check_opts7.right
@@ -6,6 +6,7 @@ CD-ROM Track List (1 - 1)
   #: MSF       LSN     Type
   1: 00:02:00  000000  data
 170: 00:06:02  000302  leadout
+Get MCN     : not available
 __________________________________
 CD Analysis Report
 CD-ROM with ISO 9660 filesystem
diff --git a/test/isofs-m1.right b/test/isofs-m1.right
index ffe58446..d52794b7 100644
--- a/test/isofs-m1.right
+++ b/test/isofs-m1.right
@@ -6,6 +6,7 @@ CD-ROM Track List (1 - 1)
   #: MSF       LSN     Type
   1: 00:02:00  000000  data
 170: 00:06:02  000302  leadout
+Get MCN     : not available
 __________________________________
 CD Analysis Report
 CD-ROM with ISO 9660 filesystem
diff --git a/test/monvoisin.right b/test/monvoisin.right
index 504ef675..ddfa3aa3 100644
--- a/test/monvoisin.right
+++ b/test/monvoisin.right
@@ -7,6 +7,7 @@ CD-ROM Track List (1 - 2)
   1: 00:02:00  000000  XA
   2: 00:18:51  001251  XA
 170: 00:39:71  002846  leadout
+Get MCN     : not available
 __________________________________
 CD Analysis Report
 CD-ROM with CD-RTOS and ISO 9660 filesystem
diff --git a/test/svcd_ogt_test_ntsc.right b/test/svcd_ogt_test_ntsc.right
index ff838903..a342bc64 100644
--- a/test/svcd_ogt_test_ntsc.right
+++ b/test/svcd_ogt_test_ntsc.right
@@ -7,6 +7,7 @@ CD-ROM Track List (1 - 2)
   1: 00:02:00  000000  XA
   2: 00:09:01  000526  XA
 170: 00:56:56  004106  leadout
+Get MCN     : not available
 __________________________________
 CD Analysis Report
 CD-ROM with CD-RTOS and ISO 9660 filesystem
@@ -48,5 +49,5 @@ ISO9660 filesystem
   - ----1xrxrxr 0 0 [fn 00] [LSN    185]      2048 Jul 14 1978 00:00  tracks.svd
 
 XA sectors   Super Video CD (SVCD) or Chaoji Video CD (CVD)
-session #2 starts at track  2, LSN:    526, ISO 9660 blocks:    376
+session #2 starts at track  2, LSN: 526, ISO 9660 blocks:    376
 ISO 9660: 376 blocks, label `SVCD_OGT_TEST_NTSC              '
diff --git a/test/svcdgs.right b/test/svcdgs.right
index f0a38688..4b939f07 100644
--- a/test/svcdgs.right
+++ b/test/svcdgs.right
@@ -7,6 +7,7 @@ CD-ROM Track List (1 - 2)
   1: 00:02:00  000000  XA
   2: 00:22:53  001553  XA
 170: 01:17:62  005687  leadout
+Get MCN     : not available
 __________________________________
 CD Analysis Report
 CD-ROM with ISO 9660 filesystem
diff --git a/test/vcd_demo.right b/test/vcd_demo.right
index 527dc370..9a141028 100644
--- a/test/vcd_demo.right
+++ b/test/vcd_demo.right
@@ -8,6 +8,7 @@ CD-ROM Track List (1 - 3)
   2: 00:17:57  001182  XA
   3: 00:24:71  001721  XA
 170: 00:30:10  002110  leadout
+Get MCN     : not available
 __________________________________
 CD Analysis Report
 CD-ROM with CD-RTOS and ISO 9660 filesystem
@@ -92,5 +93,5 @@ publisher id: `LAURENS KOEHOORN'
 preparer id: `LKVCDIMAGER 5.0.7.10(WIN32)'
 application id: `'
 
-session #2 starts at track  2, LSN:   1182, ISO 9660 blocks:   1032
+session #2 starts at track  2, LSN: 1182, ISO 9660 blocks:   1032
 ISO 9660: 1032 blocks, label `V0469                           '
diff --git a/test/videocd.right b/test/videocd.right
index d1d1ebd8..0f5c9e5b 100644
--- a/test/videocd.right
+++ b/test/videocd.right
@@ -10,6 +10,7 @@ CD-ROM Track List (1 - 5)
   4: 00:19:01  001276  XA
   5: 00:22:01  001501  XA
 170: 00:25:01  001726  leadout
+Get MCN     : not available
 __________________________________
 CD Analysis Report
 CD-ROM with CD-RTOS and ISO 9660 filesystem
@@ -56,5 +57,5 @@ ISO9660 filesystem
   - ----1xrxrxr 0 0 [fn 00] [LSN    185]      2048 Jul 14 1978 00:00  tracks.svd
 
 XA sectors   Super Video CD (SVCD) or Chaoji Video CD (CVD)
-session #2 starts at track  2, LSN:    826, ISO 9660 blocks:    676
+session #2 starts at track  2, LSN: 826, ISO 9660 blocks:    676
 ISO 9660: 676 blocks, label `SVIDEOCD                        '