diff --git a/manifest b/manifest
index 6bcf3ed8e0..6b3eab41cd 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C In\sthe\sdocumentation,\samplify\sthe\sfact\sthat\sencodings\scannot\sbe\schanged\non\sa\sdatabase\sthat\salready\sexists.\s\sTicket\s#1277.\s(CVS\s2503)
-D 2005-06-07T20:07:24
+C Changes\sto\ssupport\slinking\swithout\sa\sparser\sand\swithout\sa\sdisk\sI/O\sinterface.\s(CVS\s2504)
+D 2005-06-07T22:22:51
 F Makefile.in 8129e7f261d405db783676f9ca31e0841768c652
 F Makefile.linux-gcc 06be33b2a9ad4f005a5f42b22c4a19dab3cbb5c7
 F README 9c4e2d6706bdcc3efdd773ce752a8cdab4f90028
@@ -45,18 +45,18 @@ F src/insert.c 34c25c33f51a43644a42cc091ac967b070c6b6d5
 F src/legacy.c d58ea507bce885298a2c8c3cbb0f4bff5d47830b
 F src/main.c f61bdb0a1afeb2eff7285f4f3752e1085ecc55ed
 F src/md5.c 7ae1c39044b95de2f62e066f47bb1deb880a1070
-F src/os.h e5438be25cf96858787bf9b60fc7a2420e139ee3
+F src/os.h c4b34bd4d6fea51a420f337468b907f4edecb161
 F src/os_common.h 0e7f428ba0a6c40a61bc56c4e96f493231301b73
 F src/os_test.c 91e5f22dd89491e5e1554820e715805f43fa4ece
 F src/os_test.h 903c93554c23d88f34f667f1979e4a1cee792af3
-F src/os_unix.c 443ca9d19945a08ba1e325f00e13633b3daa5bfa
+F src/os_unix.c 45540d7ee5095566da6685d584598edee5be857c
 F src/os_unix.h 39a393252e69e72b06715c9958df05ddbc4aa971
-F src/os_win.c 2bbbe6fbb010763c3fa79d5e951afca9b138c6b5
+F src/os_win.c fe7b99cfcfb61d9bf54493ddf5857885a657fb89
 F src/os_win.h 41a946bea10f61c158ce8645e7646b29d44f122b
 F src/pager.c 841a2cdddd4275de36cda26ed9dc54ae942660ce
 F src/pager.h 0d9153d6269d60d04af3dd84a0cc0a96253cf4a4
 F src/parse.y 72cd7553f05fbc7b63ea9476108d0da6237f2818
-F src/pragma.c 0ed94a1aa982802a9cf2a932c48d99b60683fa53
+F src/pragma.c 344e50166437194c21332ada036671a3ac95652c
 F src/prepare.c d53602d2f8e097225ae7c76ec764ae68f759ba47
 F src/printf.c 3d20b21cfecadacecac3fb7274e746cb81d3d357
 F src/random.c eff68e3f257e05e81eae6c4d50a51eb88beb4ff3
@@ -281,7 +281,7 @@ F www/tclsqlite.tcl 425be741b8ae664f55cb1ef2371aab0a75109cf9
 F www/vdbe.tcl 87a31ace769f20d3627a64fa1fade7fed47b90d0
 F www/version3.tcl a99cf5f6d8bd4d5537584a2b342f0fb9fa601d8b
 F www/whentouse.tcl 528299b8316726dbcc5548e9aa0648c8b1bd055b
-P 59960a59151ae6c711dee404e60e12d4edaa3dda
-R 7ea160d72256bceb147ad6d0504408dd
+P 4704f3a19af73261ec03c0192c74a0416aeba794
+R 85f6631c1bb94d9cca30c0626cafa234
 U drh
-Z ad33796489b4694e8b4b6ddd2c758430
+Z 3dbbf934a5d9b8a10bcf167378c57366
diff --git a/manifest.uuid b/manifest.uuid
index 560fec2507..db49aee245 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-4704f3a19af73261ec03c0192c74a0416aeba794
\ No newline at end of file
+62a7353d4af4886b1561832e8b36e8e788b38834
\ No newline at end of file
diff --git a/src/os.h b/src/os.h
index e4010072db..4854964fbe 100644
--- a/src/os.h
+++ b/src/os.h
@@ -23,7 +23,8 @@
 ** N.B. MacOS means Mac Classic (or Carbon). Treat Darwin (OS X) as Unix.
 **      The MacOS build is designed to use CodeWarrior (tested with v8)
 */
-#if !defined(OS_UNIX) && !defined(OS_TEST) && !defined(OS_MEM)
+#if !defined(OS_UNIX) && !defined(OS_TEST) && !defined(OS_OTHER)
+# define OS_OTHER 0
 # ifndef OS_WIN
 #   if defined(_WIN32) || defined(WIN32) || defined(__CYGWIN__) || defined(__MINGW32__) || defined(__BORLANDC__)
 #     define OS_WIN 1
@@ -40,9 +41,6 @@
 #  define OS_WIN 0
 # endif
 #endif
-#ifndef OS_MEM
-# define OS_MEM 0
-#endif
 
 /*
 ** Invoke the appropriate operating-system specific header file.
@@ -56,8 +54,13 @@
 #if OS_WIN
 # include "os_win.h"
 #endif
-#if OS_MEM
-# include "os_mem.h"
+
+/* os_other.c and os_other.h are not delivered with SQLite.  These files
+** are place-holders that can be filled in by third-party developers to
+** implement backends to their on proprietary operating systems.
+*/
+#if OS_OTHER
+# include "os_other.h"
 #endif
 
 /* If the SET_FULLSYNC macro is not defined above, then make it
@@ -181,15 +184,19 @@ int sqlite3OsSeek(OsFile*, i64 offset);
 int sqlite3OsSync(OsFile*);
 int sqlite3OsTruncate(OsFile*, i64 size);
 int sqlite3OsFileSize(OsFile*, i64 *pSize);
-int sqlite3OsRandomSeed(char*);
-int sqlite3OsSleep(int ms);
-int sqlite3OsCurrentTime(double*);
-int sqlite3OsFileModTime(OsFile*, double*);
-void sqlite3OsEnterMutex(void);
-void sqlite3OsLeaveMutex(void);
 char *sqlite3OsFullPathname(const char*);
 int sqlite3OsLock(OsFile*, int);
 int sqlite3OsUnlock(OsFile*, int);
 int sqlite3OsCheckReservedLock(OsFile *id);
 
+
+/* The interface for file I/O is above.  Other miscellaneous functions
+** are below */
+
+int sqlite3OsRandomSeed(char*);
+int sqlite3OsSleep(int ms);
+int sqlite3OsCurrentTime(double*);
+void sqlite3OsEnterMutex(void);
+void sqlite3OsLeaveMutex(void);
+
 #endif /* _SQLITE_OS_H_ */
diff --git a/src/os_unix.c b/src/os_unix.c
index b900331bd3..9c361a1717 100644
--- a/src/os_unix.c
+++ b/src/os_unix.c
@@ -20,6 +20,18 @@
 #include <time.h>
 #include <errno.h>
 #include <unistd.h>
+
+/*
+** Do not include any of the File I/O interface procedures if the
+** SQLITE_OMIT_DISKIO macro is defined (indicating that there database
+** will be in-memory only)
+*/
+#ifndef SQLITE_OMIT_DISKIO
+
+
+/*
+** Define various macros that are missing from some systems.
+*/
 #ifndef O_LARGEFILE
 # define O_LARGEFILE 0
 #endif
@@ -34,7 +46,6 @@
 # define O_BINARY 0
 #endif
 
-
 /*
 ** The DJGPP compiler environment looks mostly like Unix, but it
 ** lacks the fcntl() system call.  So redefine fcntl() to be something
@@ -1199,6 +1210,33 @@ int sqlite3OsClose(OsFile *id){
   return SQLITE_OK;
 }
 
+/*
+** Turn a relative pathname into a full pathname.  Return a pointer
+** to the full pathname stored in space obtained from sqliteMalloc().
+** The calling function is responsible for freeing this space once it
+** is no longer needed.
+*/
+char *sqlite3OsFullPathname(const char *zRelative){
+  char *zFull = 0;
+  if( zRelative[0]=='/' ){
+    sqlite3SetString(&zFull, zRelative, (char*)0);
+  }else{
+    char zBuf[5000];
+    zBuf[0] = 0;
+    sqlite3SetString(&zFull, getcwd(zBuf, sizeof(zBuf)), "/", zRelative,
+                    (char*)0);
+  }
+  return zFull;
+}
+
+
+#endif /* SQLITE_OMIT_DISKIO */
+/***************************************************************************
+** Everything above deals with file I/O.  Everything that follows deals
+** with other miscellanous aspects of the operating system interface
+****************************************************************************/
+
+
 /*
 ** Get information to seed the random number generator.  The seed
 ** is written into the buffer zBuf[256].  The calling function must
@@ -1279,25 +1317,6 @@ void sqlite3OsLeaveMutex(){
 #endif
 }
 
-/*
-** Turn a relative pathname into a full pathname.  Return a pointer
-** to the full pathname stored in space obtained from sqliteMalloc().
-** The calling function is responsible for freeing this space once it
-** is no longer needed.
-*/
-char *sqlite3OsFullPathname(const char *zRelative){
-  char *zFull = 0;
-  if( zRelative[0]=='/' ){
-    sqlite3SetString(&zFull, zRelative, (char*)0);
-  }else{
-    char zBuf[5000];
-    zBuf[0] = 0;
-    sqlite3SetString(&zFull, getcwd(zBuf, sizeof(zBuf)), "/", zRelative,
-                    (char*)0);
-  }
-  return zFull;
-}
-
 /*
 ** The following variable, if set to a non-zero value, becomes the result
 ** returned from sqlite3OsCurrentTime().  This is used for testing.
@@ -1323,24 +1342,4 @@ int sqlite3OsCurrentTime(double *prNow){
   return 0;
 }
 
-#if 0 /* NOT USED */
-/*
-** Find the time that the file was last modified.  Write the
-** modification time and date as a Julian Day number into *prNow and
-** return SQLITE_OK.  Return SQLITE_ERROR if the modification
-** time cannot be found.
-*/
-int sqlite3OsFileModTime(OsFile *id, double *prNow){
-  int rc;
-  struct stat statbuf;
-  if( fstat(id->h, &statbuf)==0 ){
-    *prNow = statbuf.st_mtime/86400.0 + 2440587.5;
-    rc = SQLITE_OK;
-  }else{
-    rc = SQLITE_ERROR;
-  }
-  return rc;
-}
-#endif /* NOT USED */
-
 #endif /* OS_UNIX */
diff --git a/src/os_win.c b/src/os_win.c
index 6e51947afa..ea2ca26089 100644
--- a/src/os_win.c
+++ b/src/os_win.c
@@ -34,6 +34,13 @@
 */
 #include "os_common.h"
 
+/*
+** Do not include any of the File I/O interface procedures if the
+** SQLITE_OMIT_DISKIO macro is defined (indicating that there database
+** will be in-memory only)
+*/
+#ifndef SQLITE_OMIT_DISKIO
+
 /*
 ** Delete the named file
 */
@@ -625,6 +632,36 @@ int sqlite3OsUnlock(OsFile *id, int locktype){
   return rc;
 }
 
+/*
+** Turn a relative pathname into a full pathname.  Return a pointer
+** to the full pathname stored in space obtained from sqliteMalloc().
+** The calling function is responsible for freeing this space once it
+** is no longer needed.
+*/
+char *sqlite3OsFullPathname(const char *zRelative){
+  char *zNotUsed;
+  char *zFull;
+  int nByte;
+#ifdef __CYGWIN__
+  nByte = strlen(zRelative) + MAX_PATH + 1001;
+  zFull = sqliteMalloc( nByte );
+  if( zFull==0 ) return 0;
+  if( cygwin_conv_to_full_win32_path(zRelative, zFull) ) return 0;
+#else
+  nByte = GetFullPathNameA(zRelative, 0, 0, &zNotUsed) + 1;
+  zFull = sqliteMalloc( nByte );
+  if( zFull==0 ) return 0;
+  GetFullPathNameA(zRelative, nByte, zFull, &zNotUsed);
+#endif
+  return zFull;
+}
+
+#endif /* SQLITE_OMIT_DISKIO */
+/***************************************************************************
+** Everything above deals with file I/O.  Everything that follows deals
+** with other miscellanous aspects of the operating system interface
+****************************************************************************/
+
 /*
 ** Get information to seed the random number generator.  The seed
 ** is written into the buffer zBuf[256].  The calling function must
@@ -697,30 +734,6 @@ void sqlite3OsLeaveMutex(){
 #endif
 }
 
-/*
-** Turn a relative pathname into a full pathname.  Return a pointer
-** to the full pathname stored in space obtained from sqliteMalloc().
-** The calling function is responsible for freeing this space once it
-** is no longer needed.
-*/
-char *sqlite3OsFullPathname(const char *zRelative){
-  char *zNotUsed;
-  char *zFull;
-  int nByte;
-#ifdef __CYGWIN__
-  nByte = strlen(zRelative) + MAX_PATH + 1001;
-  zFull = sqliteMalloc( nByte );
-  if( zFull==0 ) return 0;
-  if( cygwin_conv_to_full_win32_path(zRelative, zFull) ) return 0;
-#else
-  nByte = GetFullPathNameA(zRelative, 0, 0, &zNotUsed) + 1;
-  zFull = sqliteMalloc( nByte );
-  if( zFull==0 ) return 0;
-  GetFullPathNameA(zRelative, nByte, zFull, &zNotUsed);
-#endif
-  return zFull;
-}
-
 /*
 ** The following variable, if set to a non-zero value, becomes the result
 ** returned from sqlite3OsCurrentTime().  This is used for testing.
@@ -751,27 +764,4 @@ int sqlite3OsCurrentTime(double *prNow){
   return 0;
 }
 
-/*
-** Find the time that the file was last modified.  Write the
-** modification time and date as a Julian Day number into *prNow and
-** return SQLITE_OK.  Return SQLITE_ERROR if the modification
-** time cannot be found.
-*/
-int sqlite3OsFileModTime(OsFile *id, double *prMTime){
-  int rc;
-  FILETIME ft;
-  /* FILETIME structure is a 64-bit value representing the number of 
-  ** 100-nanosecond intervals since January 1, 1601 (= JD 2305813.5). 
-  */
-  if( GetFileTime(id->h, 0, 0, &ft) ){
-    double t;
-    t = ((double)ft.dwHighDateTime) * 4294967296.0; 
-    *prMTime = (t + ft.dwLowDateTime)/864000000000.0 + 2305813.5;
-    rc = SQLITE_OK;
-  }else{
-    rc = SQLITE_ERROR;
-  }
-  return rc;
-}
-
 #endif /* OS_WIN */
diff --git a/src/pragma.c b/src/pragma.c
index 93f526bad9..d2116ddcfb 100644
--- a/src/pragma.c
+++ b/src/pragma.c
@@ -11,7 +11,7 @@
 *************************************************************************
 ** This file contains code used to implement the PRAGMA command.
 **
-** $Id: pragma.c,v 1.93 2005/05/22 06:49:57 danielk1977 Exp $
+** $Id: pragma.c,v 1.94 2005/06/07 22:22:51 drh Exp $
 */
 #include "sqliteInt.h"
 #include "os.h"
@@ -19,7 +19,7 @@
 
 /* Ignore this whole file if pragmas are disabled
 */
-#ifndef SQLITE_OMIT_PRAGMA
+#if !defined(SQLITE_OMIT_PRAGMA) && !defined(SQLITE_OMIT_PARSER)
 
 #if defined(SQLITE_DEBUG) || defined(SQLITE_TEST)
 # include "pager.h"
@@ -930,4 +930,4 @@ pragma_out:
   sqliteFree(zRight);
 }
 
-#endif /* SQLITE_OMIT_PRAGMA */
+#endif /* SQLITE_OMIT_PRAGMA || SQLITE_OMIT_PARSER */