1731 typedef struct sqlite3_vfs sqlite3_vfs;  typedef
1733 struct sqlite3_vfs {  struct
1737   sqlite3_vfs *pNext;      /* Next registered VFS */  argument
1740   int (*xOpen)(sqlite3_vfs*, const char *zName, sqlite3_file*,  argument
1742   int (*xDelete)(sqlite3_vfs*, const char *zName, int syncDir);  argument
1743   int (*xAccess)(sqlite3_vfs*, const char *zName, int flags, int *pResOut);  argument
1744   int (*xFullPathname)(sqlite3_vfs*, const char *zName, int nOut, char *zOut);  argument
1745   void *(*xDlOpen)(sqlite3_vfs*, const char *zFilename);  argument
1746   void (*xDlError)(sqlite3_vfs*, int nByte, char *zErrMsg);  argument
1747   void (*(*xDlSym)(sqlite3_vfs*,void*, const char *zSymbol))(void);  argument
1748   void (*xDlClose)(sqlite3_vfs*, void*);  argument
1749   int (*xRandomness)(sqlite3_vfs*, int nByte, char *zOut);  argument
1750   int (*xSleep)(sqlite3_vfs*, int microseconds);  argument
1751   int (*xCurrentTime)(sqlite3_vfs*, double*);  argument
1752   int (*xGetLastError)(sqlite3_vfs*, int, char *);  argument
1757   int (*xCurrentTimeInt64)(sqlite3_vfs*, sqlite3_int64*);  argument
1762   int (*xSetSystemCall)(sqlite3_vfs*, const char *zName, sqlite3_syscall_ptr);  argument
1763   sqlite3_syscall_ptr (*xGetSystemCall)(sqlite3_vfs*, const char *zName);  argument
1764   const char *(*xNextSystemCall)(sqlite3_vfs*, const char *zName);  argument