SQLite

  { "mkdir",        (sqlite3_syscall_ptr)mkdir,           0 },
#define osMkdir     ((int(*)(const char*,mode_t))aSyscall[18].pCurrent)

  { "rmdir",        (sqlite3_syscall_ptr)rmdir,           0 },
#define osRmdir     ((int(*)(const char*))aSyscall[19].pCurrent)

#if defined(HAVE_FCHOWN)
  { "fchown",       (sqlite3_syscall_ptr)fchown,          0 },
#else
  { "fchown",       (sqlite3_syscall_ptr)0,               0 },
#endif
#define osFchown    ((int(*)(int,uid_t,gid_t))aSyscall[20].pCurrent)

  { "geteuid",      (sqlite3_syscall_ptr)geteuid,         0 },
#define osGeteuid   ((uid_t(*)(void))aSyscall[21].pCurrent)

#if !defined(SQLITE_OMIT_WAL) || SQLITE_MAX_MMAP_SIZE>0
  { "mmap",         (sqlite3_syscall_ptr)mmap,            0 },

#if !defined(SQLITE_OMIT_WAL) || SQLITE_MAX_MMAP_SIZE>0
  { "getpagesize",  (sqlite3_syscall_ptr)unixGetpagesize, 0 },
#else
  { "getpagesize",  (sqlite3_syscall_ptr)0,               0 },
#endif
#define osGetpagesize ((int(*)(void))aSyscall[25].pCurrent)

#if defined(HAVE_READLINK)
  { "readlink",     (sqlite3_syscall_ptr)readlink,        0 },
#else
  { "readlink",     (sqlite3_syscall_ptr)0,               0 },
#endif
#define osReadlink ((ssize_t(*)(const char*,char*,size_t))aSyscall[26].pCurrent)


}; /* End of the overrideable system calls */


/*
** On some systems, calls to fchown() will trigger a message in a security
** log if they come from non-root processes.  So avoid calling fchown() if
** we are not running as root.
*/
static int robustFchown(int fd, uid_t uid, gid_t gid){
#if defined(HAVE_FCHOWN)
  return osGeteuid() ? 0 : osFchown(fd,uid,gid);
#else
  return 0;
#endif
}

/*
** This is the xSetSystemCall() method of sqlite3_vfs for all of the
** "unix" VFSes.  Return SQLITE_OK opon successfully updating the
** system call pointer, or SQLITE_NOTFOUND if there is no configurable

  ** current working directory has been unlinked.
  */
  SimulateIOError( return SQLITE_ERROR );

  assert( pVfs->mxPathname==MAX_PATHNAME );
  UNUSED_PARAMETER(pVfs);

#if defined(HAVE_READLINK)
  /* Attempt to resolve the path as if it were a symbolic link. If it is
  ** a symbolic link, the resolved path is stored in buffer zOut[]. Or, if
  ** the identified file is not a symbolic link or does not exist, then
  ** zPath is copied directly into zOut. Either way, nByte is left set to
  ** the size of the string copied into zOut[] in bytes.  */
  nByte = osReadlink(zPath, zOut, nOut-1);
  if( nByte<0 ){
    if( errno!=EINVAL && errno!=ENOENT ){
      return unixLogError(SQLITE_CANTOPEN_BKPT, "readlink", zPath);
    }
    sqlite3_snprintf(nOut, zOut, "%s", zPath);
    nByte = sqlite3Strlen30(zOut);
  }else{
    zOut[nByte] = '\0';
  }
#endif

  /* If buffer zOut[] now contains an absolute path there is nothing more
  ** to do. If it contains a relative path, do the following:
  **
  **   * move the relative path string so that it is at the end of th
  **     zOut[] buffer.
  **   * Call getcwd() to read the path of the current working directory 

#define SQLITE_HOMEGROWN_RECURSIVE_MUTEX 1
#define SQLITE_OMIT_LOAD_EXTENSION 1
#define SQLITE_ENABLE_LOCKING_STYLE 0
#define HAVE_UTIME 1
#else
/* This is not VxWorks. */
#define OS_VXWORKS 0
#define HAVE_FCHOWN 1
#define HAVE_READLINK 1
#endif /* defined(_WRS_KERNEL) */