SQLite

}
int sqlite3OsDelete(sqlite3_vfs *pVfs, const char *zPath, int dirSync){
  return pVfs->xDelete(pVfs, zPath, dirSync);
}
int sqlite3OsAccess(sqlite3_vfs *pVfs, const char *zPath, int flags){
  return pVfs->xAccess(pVfs, zPath, flags);
}
int sqlite3OsGetTempname(sqlite3_vfs *pVfs, char *zBufOut){
  return pVfs->xGetTempname(pVfs, zBufOut);
}
int sqlite3OsFullPathname(sqlite3_vfs *pVfs, const char *zPath, char *zPathOut){
  return pVfs->xFullPathname(pVfs, zPath, zPathOut);
}
void *sqlite3OsDlOpen(sqlite3_vfs *pVfs, const char *zPath){
  return pVfs->xDlOpen(pVfs, zPath);
}

/* 
** Functions for accessing sqlite3_vfs methods 
*/
int sqlite3OsOpen(sqlite3_vfs *, const char *, sqlite3_file*, int, int *);
int sqlite3OsDelete(sqlite3_vfs *, const char *, int);
int sqlite3OsAccess(sqlite3_vfs *, const char *, int);
int sqlite3OsGetTempname(sqlite3_vfs *, char *);
int sqlite3OsFullPathname(sqlite3_vfs *, const char *, char *);
void *sqlite3OsDlOpen(sqlite3_vfs *, const char *);
void sqlite3OsDlError(sqlite3_vfs *, int, char *);
void *sqlite3OsDlSym(sqlite3_vfs *, void *, const char *);
void sqlite3OsDlClose(sqlite3_vfs *, void *);
int sqlite3OsRandomness(sqlite3_vfs *, int, char *);
int sqlite3OsSleep(sqlite3_vfs *, int);

}

/*
** Create a temporary file name in zBuf.  zBuf must be allocated
** by the calling process and must be big enough to hold at least
** pVfs->mxPathname bytes.
*/
static int unixGetTempname(sqlite3_vfs *pVfs, char *zBuf){
  static const char *azDirs[] = {
     0,
     "/var/tmp",
     "/usr/tmp",
     "/tmp",
     ".",
  };

    0,                  /* pNext */
    "unix",             /* zName */
    0,                  /* pAppData */
  
    unixOpen,           /* xOpen */
    unixDelete,         /* xDelete */
    unixAccess,         /* xAccess */
    unixGetTempname,    /* xGetTempName */
    unixFullPathname,   /* xFullPathname */
    unixDlOpen,         /* xDlOpen */
    unixDlError,        /* xDlError */
    unixDlSym,          /* xDlSym */
    unixDlClose,        /* xDlClose */
    unixRandomness,     /* xRandomness */
    unixSleep,          /* xSleep */

}


/*
** Create a temporary file name in zBuf.  zBuf must be big enough to
** hold at pVfs->mxPathname characters.
*/
static int winGetTempname(sqlite3_vfs *pVfs, char *zBuf){
  static char zChars[] =
    "abcdefghijklmnopqrstuvwxyz"
    "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
    "0123456789";
  int i, j;
  char zTempPath[MAX_PATH+1];
  if( sqlite3_temp_directory ){

    0,                 /* pNext */
    "win32",           /* zName */
    0,                 /* pAppData */
  
    winOpen,           /* xOpen */
    winDelete,         /* xDelete */
    winAccess,         /* xAccess */
    winGetTempname,    /* xGetTempName */
    winFullPathname,   /* xFullPathname */
    winDlOpen,         /* xDlOpen */
    winDlError,        /* xDlError */
    winDlSym,          /* xDlSym */
    winDlClose,        /* xDlClose */
    winRandomness,     /* xRandomness */
    winSleep,          /* xSleep */

** The pager is used to access a database disk file.  It implements
** atomic commit and rollback through the use of a journal file that
** is separate from the database file.  The pager also implements file
** locking to prevent two processes from writing the same database
** file simultaneously, or one process from reading the database while
** another is writing.
**
** @(#) $Id: pager.c,v 1.389 2007/09/17 06:06:39 danielk1977 Exp $
*/
#ifndef SQLITE_OMIT_DISKIO
#include "sqliteInt.h"
#include <assert.h>
#include <string.h>

/*

      zPathname[0] = 0;
    }else
#endif
    {
      rc = sqlite3OsFullPathname(pVfs, zFilename, zPathname);
    }
  }else{
    rc = sqlite3OsGetTempname(pVfs, zPathname);
  }
  if( rc!=SQLITE_OK ){
    sqlite3_free(zPathname);
    return rc;
  }
  nPathname = strlen(zPathname);

** on how SQLite interfaces are suppose to operate.
**
** The name of this file under configuration management is "sqlite.h.in".
** The makefile makes some minor changes to this file (such as inserting
** the version number) and changes its name to "sqlite3.h" as
** part of the build process.
**
** @(#) $Id: sqlite.h.in,v 1.260 2007/09/17 06:06:39 danielk1977 Exp $
*/
#ifndef _SQLITE3_H_
#define _SQLITE3_H_
#include <stdarg.h>     /* Needed for the definition of va_list */

/*
** Make sure we can call this stuff from C++.

** to test for the existance of a file,
** or [SQLITE_ACCESS_READWRITE] to test to see
** if a file is readable and writable, or [SQLITE_ACCESS_READ]
** to test to see if a file is at least readable.  The file can be a 
** directory.
** 
** SQLite will always allocate at least mxPathname+1 byte for
** the output buffers for xGetTempname and xFullPathname.
** 
** The xRandomness(), xSleep(), and xCurrentTime() interfaces
** are not strictly a part of the filesystem, but they are
** included in the VFS structure for completeness.
** The xRandomness() function attempts to return nBytes bytes
** of good-quality randomness into zOut.  The return value is
** the actual number of bytes of randomness obtained.  The

  sqlite3_vfs *pNext;      /* Next registered VFS */
  const char *zName;       /* Name of this virtual file system */
  void *pAppData;          /* Pointer to application-specific data */
  int (*xOpen)(sqlite3_vfs*, const char *zName, sqlite3_file*,
               int flags, int *pOutFlags);
  int (*xDelete)(sqlite3_vfs*, const char *zName, int syncDir);
  int (*xAccess)(sqlite3_vfs*, const char *zName, int flags);
  int (*xGetTempname)(sqlite3_vfs*, char *zOut);
  int (*xFullPathname)(sqlite3_vfs*, const char *zName, char *zOut);
  void *(*xDlOpen)(sqlite3_vfs*, const char *zFilename);
  void (*xDlError)(sqlite3_vfs*, int nByte, char *zErrMsg);
  void *(*xDlSym)(sqlite3_vfs*,void*, const char *zSymbol);
  void (*xDlClose)(sqlite3_vfs*, void*);
  int (*xRandomness)(sqlite3_vfs*, int nByte, char *zOut);
  int (*xSleep)(sqlite3_vfs*, int microseconds);

  sqlite3_vfs *pVfs = (sqlite3_vfs *)pCfVfs->pAppData;
  return pVfs->xDelete(pVfs, zPath, dirSync);
}
static int cfAccess(sqlite3_vfs *pCfVfs, const char *zPath, int flags){
  sqlite3_vfs *pVfs = (sqlite3_vfs *)pCfVfs->pAppData;
  return pVfs->xAccess(pVfs, zPath, flags);
}
static int cfGetTempname(sqlite3_vfs *pCfVfs, char *zBufOut){
  sqlite3_vfs *pVfs = (sqlite3_vfs *)pCfVfs->pAppData;
  return pVfs->xGetTempname(pVfs, zBufOut);
}
static int cfFullPathname(sqlite3_vfs *pCfVfs, const char *zPath, char *zPathOut){
  sqlite3_vfs *pVfs = (sqlite3_vfs *)pCfVfs->pAppData;
  return pVfs->xFullPathname(pVfs, zPath, zPathOut);
}
static void *cfDlOpen(sqlite3_vfs *pCfVfs, const char *zPath){
  sqlite3_vfs *pVfs = (sqlite3_vfs *)pCfVfs->pAppData;

    0,                  /* pNext */
    "crash",            /* zName */
    0,                  /* pAppData */
  
    cfOpen,               /* xOpen */
    cfDelete,             /* xDelete */
    cfAccess,             /* xAccess */
    cfGetTempname,        /* xGetTempName */
    cfFullPathname,       /* xFullPathname */
    cfDlOpen,             /* xDlOpen */
    cfDlError,            /* xDlError */
    cfDlSym,              /* xDlSym */
    cfDlClose,            /* xDlClose */
    cfRandomness,         /* xRandomness */
    cfSleep,              /* xSleep */

    flags==SQLITE_ACCESS_READ?"read":"exists"
    , zName, ret)
  );
  pthread_mutex_unlock(&async.queueMutex);
  return ret;
}

static int asyncGetTempname(sqlite3_vfs *pAsyncVfs, char *zBufOut){
  sqlite3_vfs *pVfs = (sqlite3_vfs *)pAsyncVfs->pAppData;
  return pVfs->xGetTempname(pVfs, zBufOut);
}

/*
** Fill in zPathOut with the full path to the file identified by zPath.
*/
static int asyncFullPathname(
  sqlite3_vfs *pAsyncVfs, 

  0,                    /* mxPathname */
  0,                    /* pNext */
  "async",              /* zName */
  0,                    /* pAppData */
  asyncOpen,            /* xOpen */
  asyncDelete,          /* xDelete */
  asyncAccess,          /* xAccess */
  asyncGetTempname,     /* xGetTempName */
  asyncFullPathname,    /* xFullPathname */
  asyncDlOpen,          /* xDlOpen */
  asyncDlError,         /* xDlError */
  asyncDlSym,           /* xDlSym */
  asyncDlClose,         /* xDlClose */
  asyncRandomness,      /* xDlError */
  asyncSleep,           /* xDlSym */

/*
** Method declarations for fs_vfs.
*/
static int fsOpen(sqlite3_vfs*, const char *, sqlite3_file*, int , int *);
static int fsDelete(sqlite3_vfs*, const char *zName, int syncDir);
static int fsAccess(sqlite3_vfs*, const char *zName, int flags);
static int fsGetTempname(sqlite3_vfs*, char *zOut);
static int fsFullPathname(sqlite3_vfs*, const char *zName, char *zOut);
static void *fsDlOpen(sqlite3_vfs*, const char *zFilename);
static void fsDlError(sqlite3_vfs*, int nByte, char *zErrMsg);
static void *fsDlSym(sqlite3_vfs*,void*, const char *zSymbol);
static void fsDlClose(sqlite3_vfs*, void*);
static int fsRandomness(sqlite3_vfs*, int nByte, char *zOut);
static int fsSleep(sqlite3_vfs*, int microseconds);

    0,                                          /* mxPathname */
    0,                                          /* pNext */
    FS_VFS_NAME,                                /* zName */
    0,                                          /* pAppData */
    fsOpen,                                     /* xOpen */
    fsDelete,                                   /* xDelete */
    fsAccess,                                   /* xAccess */
    fsGetTempname,                              /* xGetTempName */
    fsFullPathname,                             /* xFullPathname */
    fsDlOpen,                                   /* xDlOpen */
    fsDlError,                                  /* xDlError */
    fsDlSym,                                    /* xDlSym */
    fsDlClose,                                  /* xDlClose */
    fsRandomness,                               /* xRandomness */
    fsSleep,                                    /* xSleep */

}

/*
** Populate buffer zBufOut with a pathname suitable for use as a 
** temporary file. zBufOut is guaranteed to point to a buffer of 
** at least (FS_MAX_PATHNAME+1) bytes.
*/
static int fsGetTempname(sqlite3_vfs *pVfs, char *zBufOut){
  sqlite3_vfs *pParent = ((fs_vfs_t *)pVfs)->pParent;
  return pParent->xGetTempname(pParent, zBufOut);
}

/*
** Populate buffer zOut with the full canonical pathname corresponding
** to the pathname in zPath. zOut is guaranteed to point to a buffer
** of at least (FS_MAX_PATHNAME+1) bytes.
*/