int flags,              /* What do we want to learn about the zPath file? */
  int *pResOut            /* Write result boolean here */
){
  UNUSED_PARAMETER(NotUsed);
  SimulateIOError( return SQLITE_IOERR_ACCESS; );
  assert( pResOut!=0 );

  /* The spec says there are three possible values for flags.  But only
  ** two of them are actually used */
  assert( flags==SQLITE_ACCESS_EXISTS || flags==SQLITE_ACCESS_READWRITE );



  if( flags==SQLITE_ACCESS_EXISTS ){
    struct stat buf;
    *pResOut = (0==osStat(zPath, &buf) && buf.st_size>0);


  }else{

    *pResOut = osAccess(zPath, W_OK|R_OK)==0;





  }
  return SQLITE_OK;
}

/*
**
*/

  int flags,              /* What do we want to learn about the zPath file? */
  int *pResOut            /* Write result boolean here */
){
  UNUSED_PARAMETER(NotUsed);
  SimulateIOError( return SQLITE_IOERR_ACCESS; );
  assert( pResOut!=0 );

  /* The spec says there are four possible values for flags.  But the
  ** SQLITE_ACCESS_READ flag is never used */
  assert( flags==SQLITE_ACCESS_EXISTS
       || flags==SQLITE_ACCESS_READWRITE
       || flags==SQLITE_ACCESS_SYMLINK );

  if( flags==SQLITE_ACCESS_EXISTS ){
    struct stat buf;
    *pResOut = (0==osStat(zPath, &buf) && buf.st_size>0);
  }else if( flags==SQLITE_ACCESS_READWRITE ){
    *pResOut = osAccess(zPath, W_OK|R_OK)==0;
  }else{
#if !defined(HAVE_LSTAT)
    *pResOut = 0;
#else
    struct stat buf;
    *pResOut = (0==osLstat(zPath, &buf) && S_ISLNK(buf.st_mode));
#endif
    assert( flags==SQLITE_ACCESS_SYMLINK );
  }
  return SQLITE_OK;
}

/*
**
*/

    case SQLITE_ACCESS_EXISTS:
      rc = attr!=INVALID_FILE_ATTRIBUTES;
      break;
    case SQLITE_ACCESS_READWRITE:
      rc = attr!=INVALID_FILE_ATTRIBUTES &&
             (attr & FILE_ATTRIBUTE_READONLY)==0;
      break;



    default:
      assert(!"Invalid flags argument");
  }
  *pResOut = rc;
  OSTRACE(("ACCESS name=%s, pResOut=%p, *pResOut=%d, rc=SQLITE_OK\n",
           zFilename, pResOut, *pResOut));
  return SQLITE_OK;

    case SQLITE_ACCESS_EXISTS:
      rc = attr!=INVALID_FILE_ATTRIBUTES;
      break;
    case SQLITE_ACCESS_READWRITE:
      rc = attr!=INVALID_FILE_ATTRIBUTES &&
             (attr & FILE_ATTRIBUTE_READONLY)==0;
      break;
    case SQLITE_ACCESS_SYMLINK:
      rc = 0;  /* No symlinks on windows */
      break;
    default:
      assert(!"Invalid flags argument");
  }
  *pResOut = rc;
  OSTRACE(("ACCESS name=%s, pResOut=%p, *pResOut=%d, rc=SQLITE_OK\n",
           zFilename, pResOut, *pResOut));
  return SQLITE_OK;

  /* Compute and store the full pathname in an allocated buffer pointed
  ** to by zPathname, length nPathname. Or, if this is a temporary file,
  ** leave both nPathname and zPathname set to 0.
  */
  if( zFilename && zFilename[0] ){
    const char *z;








    nPathname = pVfs->mxPathname+1;
    zPathname = sqlite3DbMallocRaw(0, nPathname*2);
    if( zPathname==0 ){
      return SQLITE_NOMEM_BKPT;
    }
    zPathname[0] = 0; /* Make sure initialized even if FullPathname() fails */
    rc = sqlite3OsFullPathname(pVfs, zFilename, nPathname, zPathname);

  /* Compute and store the full pathname in an allocated buffer pointed
  ** to by zPathname, length nPathname. Or, if this is a temporary file,
  ** leave both nPathname and zPathname set to 0.
  */
  if( zFilename && zFilename[0] ){
    const char *z;
    if( (vfsFlags & SQLITE_OPEN_NOFOLLOW)!=0 ){
      int isLink = 0;
      if( sqlite3OsAccess(pVfs, zFilename, SQLITE_ACCESS_SYMLINK, &isLink)==0
       && isLink
      ){
        return SQLITE_CANTOPEN_SYMLINK;
      }
    }
    nPathname = pVfs->mxPathname+1;
    zPathname = sqlite3DbMallocRaw(0, nPathname*2);
    if( zPathname==0 ){
      return SQLITE_NOMEM_BKPT;
    }
    zPathname[0] = 0; /* Make sure initialized even if FullPathname() fails */
    rc = sqlite3OsFullPathname(pVfs, zFilename, nPathname, zPathname);

  u8 doXdgOpen;          /* Invoke start/open/xdg-open in output_reset() */
  u8 nEqpLevel;          /* Depth of the EQP output graph */
  u8 eTraceType;         /* SHELL_TRACE_* value for type of trace */
  unsigned mEqpLines;    /* Mask of veritical lines in the EQP output graph */
  int outCount;          /* Revert to stdout when reaching zero */
  int cnt;               /* Number of records displayed so far */
  int lineno;            /* Line number of last line read from in */

  FILE *in;              /* Read commands from this stream */
  FILE *out;             /* Write results here */
  FILE *traceOut;        /* Output for sqlite3_trace() */
  int nErr;              /* Number of errors seen */
  int mode;              /* An output mode setting */
  int modePrior;         /* Saved mode */
  int cMode;             /* temporary output mode for the current query */
................................................................................
  "        --append        Use appendvfs to append database to the end of FILE",
#ifdef SQLITE_ENABLE_DESERIALIZE
  "        --deserialize   Load into memory useing sqlite3_deserialize()",
  "        --hexdb         Load the output of \"dbtotxt\" as an in-memory db",
  "        --maxsize N     Maximum size for --hexdb or --deserialized database",
#endif
  "        --new           Initialize FILE to an empty database",

  "        --readonly      Open FILE readonly",
  "        --zip           FILE is a ZIP archive",
  ".output ?FILE?           Send output to FILE or stdout if FILE is omitted",
  "     If FILE begins with '|' then open it as a pipe.",
  ".parameter CMD ...       Manage SQL parameter bindings",
  "   clear                   Erase all bindings",
  "   init                    Initialize the TEMP table that holds bindings",
................................................................................
        p->openMode = (u8)deduceDatabaseType(p->zDbFilename, 
                             (openFlags & OPEN_DB_ZIPFILE)!=0);
      }
    }
    switch( p->openMode ){
      case SHELL_OPEN_APPENDVFS: {
        sqlite3_open_v2(p->zDbFilename, &p->db, 
           SQLITE_OPEN_READWRITE|SQLITE_OPEN_CREATE, "apndvfs");
        break;
      }
      case SHELL_OPEN_HEXDB:
      case SHELL_OPEN_DESERIALIZE: {
        sqlite3_open(0, &p->db);
        break;
      }
      case SHELL_OPEN_ZIPFILE: {
        sqlite3_open(":memory:", &p->db);
        break;
      }
      case SHELL_OPEN_READONLY: {
        sqlite3_open_v2(p->zDbFilename, &p->db, SQLITE_OPEN_READONLY, 0);

        break;
      }
      case SHELL_OPEN_UNSPEC:
      case SHELL_OPEN_NORMAL: {
        sqlite3_open(p->zDbFilename, &p->db);

        break;
      }
    }
    globalDb = p->db;
    if( p->db==0 || SQLITE_OK!=sqlite3_errcode(p->db) ){
      utf8_printf(stderr,"Error: unable to open database \"%s\": %s\n",
          p->zDbFilename, sqlite3_errmsg(p->db));
................................................................................
    session_close_all(p);
    close_db(p->db);
    p->db = 0;
    p->zDbFilename = 0;
    sqlite3_free(p->zFreeOnClose);
    p->zFreeOnClose = 0;
    p->openMode = SHELL_OPEN_UNSPEC;

    p->szMax = 0;
    /* Check for command-line arguments */
    for(iName=1; iName<nArg && azArg[iName][0]=='-'; iName++){
      const char *z = azArg[iName];
      if( optionMatch(z,"new") ){
        newFlag = 1;
#ifdef SQLITE_HAVE_ZLIB
................................................................................
      }else if( optionMatch(z, "zip") ){
        p->openMode = SHELL_OPEN_ZIPFILE;
#endif
      }else if( optionMatch(z, "append") ){
        p->openMode = SHELL_OPEN_APPENDVFS;
      }else if( optionMatch(z, "readonly") ){
        p->openMode = SHELL_OPEN_READONLY;


#ifdef SQLITE_ENABLE_DESERIALIZE
      }else if( optionMatch(z, "deserialize") ){
        p->openMode = SHELL_OPEN_DESERIALIZE;
      }else if( optionMatch(z, "hexdb") ){
        p->openMode = SHELL_OPEN_HEXDB;
      }else if( optionMatch(z, "maxsize") && iName+1<nArg ){
        p->szMax = integerValue(azArg[++iName]);
................................................................................
#endif
  "   -memtrace            trace all memory allocations and deallocations\n"
  "   -mmap N              default mmap size set to N\n"
#ifdef SQLITE_ENABLE_MULTIPLEX
  "   -multiplex           enable the multiplexor VFS\n"
#endif
  "   -newline SEP         set output row separator. Default: '\\n'\n"

  "   -nullvalue TEXT      set text string for NULL values. Default ''\n"
  "   -pagecache SIZE N    use N slots of SZ bytes each for page cache memory\n"
  "   -quote               set output mode to 'quote'\n"
  "   -readonly            open the database read-only\n"
  "   -separator SEP       set output column separator. Default: '|'\n"
#ifdef SQLITE_ENABLE_SORTER_REFERENCES
  "   -sorterref SIZE      sorter references threshold size\n"
................................................................................
    }else if( strcmp(z,"-deserialize")==0 ){
      data.openMode = SHELL_OPEN_DESERIALIZE;
    }else if( strcmp(z,"-maxsize")==0 && i+1<argc ){
      data.szMax = integerValue(argv[++i]);
#endif
    }else if( strcmp(z,"-readonly")==0 ){
      data.openMode = SHELL_OPEN_READONLY;


#if !defined(SQLITE_OMIT_VIRTUALTABLE) && defined(SQLITE_HAVE_ZLIB)
    }else if( strncmp(z, "-A",2)==0 ){
      /* All remaining command-line arguments are passed to the ".archive"
      ** command, so ignore them */
      break;
#endif
    }else if( strcmp(z, "-memtrace")==0 ){
................................................................................
    }else if( strcmp(z,"-deserialize")==0 ){
      data.openMode = SHELL_OPEN_DESERIALIZE;
    }else if( strcmp(z,"-maxsize")==0 && i+1<argc ){
      data.szMax = integerValue(argv[++i]);
#endif
    }else if( strcmp(z,"-readonly")==0 ){
      data.openMode = SHELL_OPEN_READONLY;


    }else if( strcmp(z,"-ascii")==0 ){
      data.mode = MODE_Ascii;
      sqlite3_snprintf(sizeof(data.colSeparator), data.colSeparator,
                       SEP_Unit);
      sqlite3_snprintf(sizeof(data.rowSeparator), data.rowSeparator,
                       SEP_Record);
    }else if( strcmp(z,"-separator")==0 ){

  u8 doXdgOpen;          /* Invoke start/open/xdg-open in output_reset() */
  u8 nEqpLevel;          /* Depth of the EQP output graph */
  u8 eTraceType;         /* SHELL_TRACE_* value for type of trace */
  unsigned mEqpLines;    /* Mask of veritical lines in the EQP output graph */
  int outCount;          /* Revert to stdout when reaching zero */
  int cnt;               /* Number of records displayed so far */
  int lineno;            /* Line number of last line read from in */
  int openFlags;         /* Additional flags to open.  (SQLITE_OPEN_NOFOLLOW) */
  FILE *in;              /* Read commands from this stream */
  FILE *out;             /* Write results here */
  FILE *traceOut;        /* Output for sqlite3_trace() */
  int nErr;              /* Number of errors seen */
  int mode;              /* An output mode setting */
  int modePrior;         /* Saved mode */
  int cMode;             /* temporary output mode for the current query */
................................................................................
  "        --append        Use appendvfs to append database to the end of FILE",
#ifdef SQLITE_ENABLE_DESERIALIZE
  "        --deserialize   Load into memory useing sqlite3_deserialize()",
  "        --hexdb         Load the output of \"dbtotxt\" as an in-memory db",
  "        --maxsize N     Maximum size for --hexdb or --deserialized database",
#endif
  "        --new           Initialize FILE to an empty database",
  "        --nofollow      Do not follow symbolic links",
  "        --readonly      Open FILE readonly",
  "        --zip           FILE is a ZIP archive",
  ".output ?FILE?           Send output to FILE or stdout if FILE is omitted",
  "     If FILE begins with '|' then open it as a pipe.",
  ".parameter CMD ...       Manage SQL parameter bindings",
  "   clear                   Erase all bindings",
  "   init                    Initialize the TEMP table that holds bindings",
................................................................................
        p->openMode = (u8)deduceDatabaseType(p->zDbFilename, 
                             (openFlags & OPEN_DB_ZIPFILE)!=0);
      }
    }
    switch( p->openMode ){
      case SHELL_OPEN_APPENDVFS: {
        sqlite3_open_v2(p->zDbFilename, &p->db, 
           SQLITE_OPEN_READWRITE|SQLITE_OPEN_CREATE|p->openFlags, "apndvfs");
        break;
      }
      case SHELL_OPEN_HEXDB:
      case SHELL_OPEN_DESERIALIZE: {
        sqlite3_open(0, &p->db);
        break;
      }
      case SHELL_OPEN_ZIPFILE: {
        sqlite3_open(":memory:", &p->db);
        break;
      }
      case SHELL_OPEN_READONLY: {
        sqlite3_open_v2(p->zDbFilename, &p->db,
            SQLITE_OPEN_READONLY|p->openFlags, 0);
        break;
      }
      case SHELL_OPEN_UNSPEC:
      case SHELL_OPEN_NORMAL: {
        sqlite3_open_v2(p->zDbFilename, &p->db,
           SQLITE_OPEN_READWRITE|SQLITE_OPEN_CREATE|p->openFlags, 0);
        break;
      }
    }
    globalDb = p->db;
    if( p->db==0 || SQLITE_OK!=sqlite3_errcode(p->db) ){
      utf8_printf(stderr,"Error: unable to open database \"%s\": %s\n",
          p->zDbFilename, sqlite3_errmsg(p->db));
................................................................................
    session_close_all(p);
    close_db(p->db);
    p->db = 0;
    p->zDbFilename = 0;
    sqlite3_free(p->zFreeOnClose);
    p->zFreeOnClose = 0;
    p->openMode = SHELL_OPEN_UNSPEC;
    p->openFlags = 0;
    p->szMax = 0;
    /* Check for command-line arguments */
    for(iName=1; iName<nArg && azArg[iName][0]=='-'; iName++){
      const char *z = azArg[iName];
      if( optionMatch(z,"new") ){
        newFlag = 1;
#ifdef SQLITE_HAVE_ZLIB
................................................................................
      }else if( optionMatch(z, "zip") ){
        p->openMode = SHELL_OPEN_ZIPFILE;
#endif
      }else if( optionMatch(z, "append") ){
        p->openMode = SHELL_OPEN_APPENDVFS;
      }else if( optionMatch(z, "readonly") ){
        p->openMode = SHELL_OPEN_READONLY;
      }else if( optionMatch(z, "nofollow") ){
        p->openFlags |= SQLITE_OPEN_NOFOLLOW;
#ifdef SQLITE_ENABLE_DESERIALIZE
      }else if( optionMatch(z, "deserialize") ){
        p->openMode = SHELL_OPEN_DESERIALIZE;
      }else if( optionMatch(z, "hexdb") ){
        p->openMode = SHELL_OPEN_HEXDB;
      }else if( optionMatch(z, "maxsize") && iName+1<nArg ){
        p->szMax = integerValue(azArg[++iName]);
................................................................................
#endif
  "   -memtrace            trace all memory allocations and deallocations\n"
  "   -mmap N              default mmap size set to N\n"
#ifdef SQLITE_ENABLE_MULTIPLEX
  "   -multiplex           enable the multiplexor VFS\n"
#endif
  "   -newline SEP         set output row separator. Default: '\\n'\n"
  "   -nofollow            refuse to open symbolic links to database files\n"
  "   -nullvalue TEXT      set text string for NULL values. Default ''\n"
  "   -pagecache SIZE N    use N slots of SZ bytes each for page cache memory\n"
  "   -quote               set output mode to 'quote'\n"
  "   -readonly            open the database read-only\n"
  "   -separator SEP       set output column separator. Default: '|'\n"
#ifdef SQLITE_ENABLE_SORTER_REFERENCES
  "   -sorterref SIZE      sorter references threshold size\n"
................................................................................
    }else if( strcmp(z,"-deserialize")==0 ){
      data.openMode = SHELL_OPEN_DESERIALIZE;
    }else if( strcmp(z,"-maxsize")==0 && i+1<argc ){
      data.szMax = integerValue(argv[++i]);
#endif
    }else if( strcmp(z,"-readonly")==0 ){
      data.openMode = SHELL_OPEN_READONLY;
    }else if( strcmp(z,"-nofollow")==0 ){
      data.openFlags = SQLITE_OPEN_NOFOLLOW;
#if !defined(SQLITE_OMIT_VIRTUALTABLE) && defined(SQLITE_HAVE_ZLIB)
    }else if( strncmp(z, "-A",2)==0 ){
      /* All remaining command-line arguments are passed to the ".archive"
      ** command, so ignore them */
      break;
#endif
    }else if( strcmp(z, "-memtrace")==0 ){
................................................................................
    }else if( strcmp(z,"-deserialize")==0 ){
      data.openMode = SHELL_OPEN_DESERIALIZE;
    }else if( strcmp(z,"-maxsize")==0 && i+1<argc ){
      data.szMax = integerValue(argv[++i]);
#endif
    }else if( strcmp(z,"-readonly")==0 ){
      data.openMode = SHELL_OPEN_READONLY;
    }else if( strcmp(z,"-nofollow")==0 ){
      data.openFlags |= SQLITE_OPEN_NOFOLLOW;
    }else if( strcmp(z,"-ascii")==0 ){
      data.mode = MODE_Ascii;
      sqlite3_snprintf(sizeof(data.colSeparator), data.colSeparator,
                       SEP_Unit);
      sqlite3_snprintf(sizeof(data.rowSeparator), data.rowSeparator,
                       SEP_Record);
    }else if( strcmp(z,"-separator")==0 ){

#define SQLITE_BUSY_RECOVERY           (SQLITE_BUSY   |  (1<<8))
#define SQLITE_BUSY_SNAPSHOT           (SQLITE_BUSY   |  (2<<8))
#define SQLITE_CANTOPEN_NOTEMPDIR      (SQLITE_CANTOPEN | (1<<8))
#define SQLITE_CANTOPEN_ISDIR          (SQLITE_CANTOPEN | (2<<8))
#define SQLITE_CANTOPEN_FULLPATH       (SQLITE_CANTOPEN | (3<<8))
#define SQLITE_CANTOPEN_CONVPATH       (SQLITE_CANTOPEN | (4<<8))
#define SQLITE_CANTOPEN_DIRTYWAL       (SQLITE_CANTOPEN | (5<<8)) /* Not Used */

#define SQLITE_CORRUPT_VTAB            (SQLITE_CORRUPT | (1<<8))
#define SQLITE_CORRUPT_SEQUENCE        (SQLITE_CORRUPT | (2<<8))
#define SQLITE_READONLY_RECOVERY       (SQLITE_READONLY | (1<<8))
#define SQLITE_READONLY_CANTLOCK       (SQLITE_READONLY | (2<<8))
#define SQLITE_READONLY_ROLLBACK       (SQLITE_READONLY | (3<<8))
#define SQLITE_READONLY_DBMOVED        (SQLITE_READONLY | (4<<8))
#define SQLITE_READONLY_CANTINIT       (SQLITE_READONLY | (5<<8))
................................................................................
#define SQLITE_OPEN_SUBJOURNAL       0x00002000  /* VFS only */
#define SQLITE_OPEN_MASTER_JOURNAL   0x00004000  /* VFS only */
#define SQLITE_OPEN_NOMUTEX          0x00008000  /* Ok for sqlite3_open_v2() */
#define SQLITE_OPEN_FULLMUTEX        0x00010000  /* Ok for sqlite3_open_v2() */
#define SQLITE_OPEN_SHAREDCACHE      0x00020000  /* Ok for sqlite3_open_v2() */
#define SQLITE_OPEN_PRIVATECACHE     0x00040000  /* Ok for sqlite3_open_v2() */
#define SQLITE_OPEN_WAL              0x00080000  /* VFS only */


/* Reserved:                         0x00F00000 */

/*
** CAPI3REF: Device Characteristics
**
** The xDeviceCharacteristics method of the [sqlite3_io_methods]
................................................................................
** checks whether the file is readable.  The SQLITE_ACCESS_READ constant is
** currently unused, though it might be used in a future release of
** SQLite.
*/
#define SQLITE_ACCESS_EXISTS    0
#define SQLITE_ACCESS_READWRITE 1   /* Used by PRAGMA temp_store_directory */
#define SQLITE_ACCESS_READ      2   /* Unused */


/*
** CAPI3REF: Flags for the xShmLock VFS method
**
** These integer constants define the various locking operations
** allowed by the xShmLock method of [sqlite3_io_methods].  The
** following are the only legal combinations of flags to the

#define SQLITE_BUSY_RECOVERY           (SQLITE_BUSY   |  (1<<8))
#define SQLITE_BUSY_SNAPSHOT           (SQLITE_BUSY   |  (2<<8))
#define SQLITE_CANTOPEN_NOTEMPDIR      (SQLITE_CANTOPEN | (1<<8))
#define SQLITE_CANTOPEN_ISDIR          (SQLITE_CANTOPEN | (2<<8))
#define SQLITE_CANTOPEN_FULLPATH       (SQLITE_CANTOPEN | (3<<8))
#define SQLITE_CANTOPEN_CONVPATH       (SQLITE_CANTOPEN | (4<<8))
#define SQLITE_CANTOPEN_DIRTYWAL       (SQLITE_CANTOPEN | (5<<8)) /* Not Used */
#define SQLITE_CANTOPEN_SYMLINK        (SQLITE_CANTOPEN | (6<<8))
#define SQLITE_CORRUPT_VTAB            (SQLITE_CORRUPT | (1<<8))
#define SQLITE_CORRUPT_SEQUENCE        (SQLITE_CORRUPT | (2<<8))
#define SQLITE_READONLY_RECOVERY       (SQLITE_READONLY | (1<<8))
#define SQLITE_READONLY_CANTLOCK       (SQLITE_READONLY | (2<<8))
#define SQLITE_READONLY_ROLLBACK       (SQLITE_READONLY | (3<<8))
#define SQLITE_READONLY_DBMOVED        (SQLITE_READONLY | (4<<8))
#define SQLITE_READONLY_CANTINIT       (SQLITE_READONLY | (5<<8))
................................................................................
#define SQLITE_OPEN_SUBJOURNAL       0x00002000  /* VFS only */
#define SQLITE_OPEN_MASTER_JOURNAL   0x00004000  /* VFS only */
#define SQLITE_OPEN_NOMUTEX          0x00008000  /* Ok for sqlite3_open_v2() */
#define SQLITE_OPEN_FULLMUTEX        0x00010000  /* Ok for sqlite3_open_v2() */
#define SQLITE_OPEN_SHAREDCACHE      0x00020000  /* Ok for sqlite3_open_v2() */
#define SQLITE_OPEN_PRIVATECACHE     0x00040000  /* Ok for sqlite3_open_v2() */
#define SQLITE_OPEN_WAL              0x00080000  /* VFS only */
#define SQLITE_OPEN_NOFOLLOW         0x01000000  /* Ok for sqlite3_open_v2() */

/* Reserved:                         0x00F00000 */

/*
** CAPI3REF: Device Characteristics
**
** The xDeviceCharacteristics method of the [sqlite3_io_methods]
................................................................................
** checks whether the file is readable.  The SQLITE_ACCESS_READ constant is
** currently unused, though it might be used in a future release of
** SQLite.
*/
#define SQLITE_ACCESS_EXISTS    0
#define SQLITE_ACCESS_READWRITE 1   /* Used by PRAGMA temp_store_directory */
#define SQLITE_ACCESS_READ      2   /* Unused */
#define SQLITE_ACCESS_SYMLINK   3   /* Test if file is symbolic link */

/*
** CAPI3REF: Flags for the xShmLock VFS method
**
** These integer constants define the various locking operations
** allowed by the xShmLock method of [sqlite3_io_methods].  The
** following are the only legal combinations of flags to the

*/
static int sqliteCmdUsage(
  Tcl_Interp *interp,
  Tcl_Obj *const*objv
){
  Tcl_WrongNumArgs(interp, 1, objv,
    "HANDLE ?FILENAME? ?-vfs VFSNAME? ?-readonly BOOLEAN? ?-create BOOLEAN?"

    " ?-nomutex BOOLEAN? ?-fullmutex BOOLEAN? ?-uri BOOLEAN?"
#if defined(SQLITE_HAS_CODEC) && !defined(SQLITE_OMIT_CODEC_FROM_TCL)
    " ?-key CODECKEY?"
#endif
  );
  return TCL_ERROR;
}

/*
**   sqlite3 DBNAME FILENAME ?-vfs VFSNAME? ?-key KEY? ?-readonly BOOLEAN?
**                           ?-create BOOLEAN? ?-nomutex BOOLEAN?

**
** This is the main Tcl command.  When the "sqlite" Tcl command is
** invoked, this routine runs to process that command.
**
** The first argument, DBNAME, is an arbitrary name for a new
** database connection.  This command creates a new command named
** DBNAME that is used to control that connection.  The database
................................................................................
    }else if( strcmp(zArg, "-create")==0 ){
      int b;
      if( Tcl_GetBooleanFromObj(interp, objv[i], &b) ) return TCL_ERROR;
      if( b && (flags & SQLITE_OPEN_READONLY)==0 ){
        flags |= SQLITE_OPEN_CREATE;
      }else{
        flags &= ~SQLITE_OPEN_CREATE;








      }
    }else if( strcmp(zArg, "-nomutex")==0 ){
      int b;
      if( Tcl_GetBooleanFromObj(interp, objv[i], &b) ) return TCL_ERROR;
      if( b ){
        flags |= SQLITE_OPEN_NOMUTEX;
        flags &= ~SQLITE_OPEN_FULLMUTEX;

*/
static int sqliteCmdUsage(
  Tcl_Interp *interp,
  Tcl_Obj *const*objv
){
  Tcl_WrongNumArgs(interp, 1, objv,
    "HANDLE ?FILENAME? ?-vfs VFSNAME? ?-readonly BOOLEAN? ?-create BOOLEAN?"
    " ?-nofollow BOOLEAN?"
    " ?-nomutex BOOLEAN? ?-fullmutex BOOLEAN? ?-uri BOOLEAN?"
#if defined(SQLITE_HAS_CODEC) && !defined(SQLITE_OMIT_CODEC_FROM_TCL)
    " ?-key CODECKEY?"
#endif
  );
  return TCL_ERROR;
}

/*
**   sqlite3 DBNAME FILENAME ?-vfs VFSNAME? ?-key KEY? ?-readonly BOOLEAN?
**                           ?-create BOOLEAN? ?-nomutex BOOLEAN?
**                           ?-nofollow BOOLEAN?
**
** This is the main Tcl command.  When the "sqlite" Tcl command is
** invoked, this routine runs to process that command.
**
** The first argument, DBNAME, is an arbitrary name for a new
** database connection.  This command creates a new command named
** DBNAME that is used to control that connection.  The database
................................................................................
    }else if( strcmp(zArg, "-create")==0 ){
      int b;
      if( Tcl_GetBooleanFromObj(interp, objv[i], &b) ) return TCL_ERROR;
      if( b && (flags & SQLITE_OPEN_READONLY)==0 ){
        flags |= SQLITE_OPEN_CREATE;
      }else{
        flags &= ~SQLITE_OPEN_CREATE;
      }
    }else if( strcmp(zArg, "-nofollow")==0 ){
      int b;
      if( Tcl_GetBooleanFromObj(interp, objv[i], &b) ) return TCL_ERROR;
      if( b ){
        flags |= SQLITE_OPEN_NOFOLLOW;
      }else{
        flags &= ~SQLITE_OPEN_NOFOLLOW;
      }
    }else if( strcmp(zArg, "-nomutex")==0 ){
      int b;
      if( Tcl_GetBooleanFromObj(interp, objv[i], &b) ) return TCL_ERROR;
      if( b ){
        flags |= SQLITE_OPEN_NOMUTEX;
        flags &= ~SQLITE_OPEN_FULLMUTEX;

){
  int rc;                         /* access() return code */
  int eAccess = F_OK;             /* Second argument to access() */

  assert( flags==SQLITE_ACCESS_EXISTS       /* access(zPath, F_OK) */
       || flags==SQLITE_ACCESS_READ         /* access(zPath, R_OK) */
       || flags==SQLITE_ACCESS_READWRITE    /* access(zPath, R_OK|W_OK) */

  );






  if( flags==SQLITE_ACCESS_READWRITE ) eAccess = R_OK|W_OK;
  if( flags==SQLITE_ACCESS_READ )      eAccess = R_OK;

  rc = access(zPath, eAccess);
  *pResOut = (rc==0);
  return SQLITE_OK;
}

){
  int rc;                         /* access() return code */
  int eAccess = F_OK;             /* Second argument to access() */

  assert( flags==SQLITE_ACCESS_EXISTS       /* access(zPath, F_OK) */
       || flags==SQLITE_ACCESS_READ         /* access(zPath, R_OK) */
       || flags==SQLITE_ACCESS_READWRITE    /* access(zPath, R_OK|W_OK) */
       || flags==SQLITE_ACCESS_SYMLINK      /* Always false */
  );

  if( flags==SQLITE_ACCESS_SYMLINK ){
    /* For this demo implementation, assume that symlinks do not exist. */
    *pResOut = 0;
    return SQLITE_OK;
  }
  if( flags==SQLITE_ACCESS_READWRITE ) eAccess = R_OK|W_OK;
  if( flags==SQLITE_ACCESS_READ )      eAccess = R_OK;

  rc = access(zPath, eAccess);
  *pResOut = (rc==0);
  return SQLITE_OK;
}

  Testvfs *p = (Testvfs *)pVfs->pAppData;
  if( p->pScript && p->mask&TESTVFS_ACCESS_MASK ){
    int rc;
    char *zArg = 0;
    if( flags==SQLITE_ACCESS_EXISTS ) zArg = "SQLITE_ACCESS_EXISTS";
    if( flags==SQLITE_ACCESS_READWRITE ) zArg = "SQLITE_ACCESS_READWRITE";
    if( flags==SQLITE_ACCESS_READ ) zArg = "SQLITE_ACCESS_READ";

    tvfsExecTcl(p, "xAccess", 
        Tcl_NewStringObj(zPath, -1), Tcl_NewStringObj(zArg, -1), 0, 0
    );
    if( tvfsResultCode(p, &rc) ){
      if( rc!=SQLITE_OK ) return rc;
    }else{
      Tcl_Interp *interp = p->interp;

  Testvfs *p = (Testvfs *)pVfs->pAppData;
  if( p->pScript && p->mask&TESTVFS_ACCESS_MASK ){
    int rc;
    char *zArg = 0;
    if( flags==SQLITE_ACCESS_EXISTS ) zArg = "SQLITE_ACCESS_EXISTS";
    if( flags==SQLITE_ACCESS_READWRITE ) zArg = "SQLITE_ACCESS_READWRITE";
    if( flags==SQLITE_ACCESS_READ ) zArg = "SQLITE_ACCESS_READ";
    if( flags==SQLITE_ACCESS_SYMLINK ) zArg = "SQLITE_ACCESS_SYMLINK";
    tvfsExecTcl(p, "xAccess", 
        Tcl_NewStringObj(zPath, -1), Tcl_NewStringObj(zArg, -1), 0, 0
    );
    if( tvfsResultCode(p, &rc) ){
      if( rc!=SQLITE_OK ) return rc;
    }else{
      Tcl_Interp *interp = p->interp;

forcedelete test.db2
do_test 1.1 {
  file link test.db2 test.db
  sqlite3 db2 test.db2
  sqlite3_db_filename db2 main
} [file join [pwd] test.db]




















# Test that if the symlink points to a file that does not exists, it is
# created when it is opened.
#
do_test 1.2.1 {
  db2 close
  db close
  forcedelete test.db
  file exists test.db
} 0
do_test 1.2.2 {
  sqlite3 db2 test.db2
  file exists test.db

forcedelete test.db2
do_test 1.1 {
  file link test.db2 test.db
  sqlite3 db2 test.db2
  sqlite3_db_filename db2 main
} [file join [pwd] test.db]

# But not with the -nofollow flag
#
do_test 1.1.2 {
  db2 close
  set rc [catch {sqlite3 db2 test.db2 -nofollow 1} msg]
  lappend rc $msg
} {1 {unable to open database file}}

# If the main database is successfully opened with -nofollow, then -nofollow
# is also used for ATTACH.
#
do_test 1.1.3 {
  catch {db2 close}
  sqlite3 db2 test.db -nofollow 1
} {}
do_test 1.1.4 {
  catchsql {ATTACH 'test.db2' AS aux1;} db2
} {1 {unable to open database: test.db2}}

# Test that if the symlink points to a file that does not exists, it is
# created when it is opened.
#
do_test 1.2.1 {
  catch {db2 close}
  db close
  forcedelete test.db
  file exists test.db
} 0
do_test 1.2.2 {
  sqlite3 db2 test.db2
  file exists test.db

set testdir [file dirname $argv0]
source $testdir/tester.tcl
set testprefix tcl

# Check the error messages generated by tclsqlite
#
set r "sqlite_orig HANDLE ?FILENAME? ?-vfs VFSNAME? ?-readonly BOOLEAN? ?-create BOOLEAN? ?-nomutex BOOLEAN? ?-fullmutex BOOLEAN? ?-uri BOOLEAN?"
if {[sqlite3 -has-codec]} {
  append r " ?-key CODECKEY?"
}
do_test tcl-1.1 {
  set v [catch {sqlite3 -bogus} msg]
  regsub {really_sqlite3} $msg {sqlite3} msg
  lappend v $msg

set testdir [file dirname $argv0]
source $testdir/tester.tcl
set testprefix tcl

# Check the error messages generated by tclsqlite
#
set r "sqlite_orig HANDLE ?FILENAME? ?-vfs VFSNAME? ?-readonly BOOLEAN? ?-create BOOLEAN? ?-nofollow BOOLEAN? ?-nomutex BOOLEAN? ?-fullmutex BOOLEAN? ?-uri BOOLEAN?"
if {[sqlite3 -has-codec]} {
  append r " ?-key CODECKEY?"
}
do_test tcl-1.1 {
  set v [catch {sqlite3 -bogus} msg]
  regsub {really_sqlite3} $msg {sqlite3} msg
  lappend v $msg