SQLite

** 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 1.333 2007/05/03 17:18:37 drh Exp $
*/
#ifndef SQLITE_OMIT_DISKIO
#include "sqliteInt.h"
#include "os.h"
#include "pager.h"
#include <assert.h>
#include <string.h>

        sqlite3PagerPagecount(pPager);

        if( pPager->errCode ){
          return pPager->errCode;
        }

        if( pPager->dbSize>0 ){
          IOTRACE(("CKVERS %p %d\n", pPager, sizeof(dbFileVers)));
          rc = sqlite3OsSeek(pPager->fd, 24);
          if( rc!=SQLITE_OK ){
            return rc;
          }
          rc = sqlite3OsRead(pPager->fd, &dbFileVers, sizeof(dbFileVers));
          if( rc!=SQLITE_OK ){
            return rc;

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains code to implement the "sqlite" command line
** utility for accessing SQLite databases.
**
** $Id: shell.c,v 1.161 2007/05/03 17:18:38 drh Exp $
*/
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <assert.h>
#include "sqlite3.h"
#include <ctype.h>

  ".echo ON|OFF           Turn command echo on or off\n"
  ".exit                  Exit this program\n"
  ".explain ON|OFF        Turn output mode suitable for EXPLAIN on or off.\n"
  ".header(s) ON|OFF      Turn display of headers on or off\n"
  ".help                  Show this message\n"
  ".import FILE TABLE     Import data from FILE into TABLE\n"
  ".indices TABLE         Show names of all indices on TABLE\n"
#ifdef SQLITE_ENABLE_IOTRACE
  ".iotrace FILE          Enable I/O diagnostic logging to FILE\n"
#endif
#ifndef SQLITE_OMIT_LOAD_EXTENSION
  ".load FILE ?ENTRY?     Load an extension library\n"
#endif
  ".mode MODE ?TABLE?     Set output mode where MODE is one of:\n"
  "                         csv      Comma-separated values\n"
  "                         column   Left-aligned columns.  (See .width)\n"
  "                         html     HTML <table> code\n"

    zShellStatic = 0;
    if( zErrMsg ){
      fprintf(stderr,"Error: %s\n", zErrMsg);
      sqlite3_free(zErrMsg);
    }
  }else

#ifdef SQLITE_ENABLE_IOTRACE
  if( c=='i' && strncmp(azArg[0], "iotrace", n)==0 ){
    extern void (*sqlite3_io_trace)(const char*, ...);
    if( iotrace && iotrace!=stdout ) fclose(iotrace);
    iotrace = 0;
    if( nArg<2 ){
      sqlite3_io_trace = 0;
    }else if( strcmp(azArg[1], "-")==0 ){
      sqlite3_io_trace = iotracePrintf;
      iotrace = stdout;
    }else{
      iotrace = fopen(azArg[1], "w");
      if( iotrace==0 ){
        fprintf(stderr, "cannot open \"%s\"\n", azArg[1]);
        sqlite3_io_trace = 0;
      }else{
        sqlite3_io_trace = iotracePrintf;
      }
    }
  }else
#endif

#ifndef SQLITE_OMIT_LOAD_EXTENSION
  if( c=='l' && strncmp(azArg[0], "load", n)==0 && nArg>=2 ){
    const char *zFile, *zProc;
    char *zErrMsg = 0;
    int rc;
    zFile = azArg[1];