SQLite

  int rc;
  PgHdr *pPg;                   /* An existing page in the cache */
  Pgno pgno;                    /* The page number of a page in journal */
  u32 cksum;                    /* Checksum used for sanity checking */
  char *aData;                  /* Temporary storage for the page */
  sqlite3_file *jfd;            /* The file descriptor for the journal file */
  int isSynced;                 /* True if journal page is synced */
#ifdef SQLITE_HAS_CODEC
  /* The jrnlEnc flag is true if Journal pages should be passed through
  ** the codec.  It is false for pure in-memory journals. */
  const int jrnlEnc = (isMainJrnl || pPager->subjInMemory==0);
#endif

  assert( (isMainJrnl&~1)==0 );      /* isMainJrnl is 0 or 1 */
  assert( (isSavepnt&~1)==0 );       /* isSavepnt is 0 or 1 */
  assert( isMainJrnl || pDone );     /* pDone always used on sub-journals */
  assert( isSavepnt || pDone==0 );   /* pDone never used on non-savepoint */

  aData = pPager->pTmpSpace;

    /* Write the data read from the journal back into the database file.
    ** This is usually safe even for an encrypted database - as the data
    ** was encrypted before it was written to the journal file. The exception
    ** is if the data was just read from an in-memory sub-journal. In that
    ** case it must be encrypted here before it is copied into the database
    ** file.  */
#ifdef SQLITE_HAS_CODEC
    if( !jrnlEnc ){
      CODEC2(pPager, aData, pgno, 7, rc=SQLITE_NOMEM_BKPT, aData);
      rc = sqlite3OsWrite(pPager->fd, (u8 *)aData, pPager->pageSize, ofst);
      CODEC1(pPager, aData, pgno, 3, rc=SQLITE_NOMEM_BKPT);
    }else
#endif
    rc = sqlite3OsWrite(pPager->fd, (u8 *)aData, pPager->pageSize, ofst);

    if( pgno>pPager->dbFileSize ){
      pPager->dbFileSize = pgno;
    }
    if( pPager->pBackup ){
#ifdef SQLITE_HAS_CODEC
      if( jrnlEnc ){
        CODEC1(pPager, aData, pgno, 3, rc=SQLITE_NOMEM_BKPT);
        sqlite3BackupUpdate(pPager->pBackup, pgno, (u8*)aData);
        CODEC2(pPager, aData, pgno, 7, rc=SQLITE_NOMEM_BKPT,aData);
      }else
#endif
      sqlite3BackupUpdate(pPager->pBackup, pgno, (u8*)aData);
    }
  }else if( !isMainJrnl && pPg==0 ){
    /* If this is a rollback of a savepoint and data was not written to
    ** the database and the page is not in-memory, there is a potential
    ** problem. When the page is next fetched by the b-tree layer, it 
    ** will be read from the database file, which may or may not be 
    ** current. 

    /* If this was page 1, then restore the value of Pager.dbFileVers.
    ** Do this before any decoding. */
    if( pgno==1 ){
      memcpy(&pPager->dbFileVers, &((u8*)pData)[24],sizeof(pPager->dbFileVers));
    }

    /* Decode the page just read from disk */
#if SQLITE_HAS_CODEC
    if( jrnlEnc ){ CODEC1(pPager, pData, pPg->pgno, 3, rc=SQLITE_NOMEM_BKPT); }
#endif
    sqlite3PcacheRelease(pPg);
  }
  return rc;
}

/*
** Parameter zMaster is the name of a master journal file. A single journal

    /* If the sub-journal was opened successfully (or was already open),
    ** write the journal record into the file.  */
    if( rc==SQLITE_OK ){
      void *pData = pPg->pData;
      i64 offset = (i64)pPager->nSubRec*(4+pPager->pageSize);
      char *pData2;

#if SQLITE_HAS_CODEC   
      if( !pPager->subjInMemory ){


        CODEC2(pPager, pData, pPg->pgno, 7, return SQLITE_NOMEM_BKPT, pData2);
      }else
#endif
      pData2 = pData;
      PAGERTRACE(("STMT-JOURNAL %d page %d\n", PAGERID(pPager), pPg->pgno));
      rc = write32bits(pPager->sjfd, offset, pPg->pgno);
      if( rc==SQLITE_OK ){
        rc = sqlite3OsWrite(pPager->sjfd, pData2, pPager->pageSize, offset+4);
      }
    }
  }