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copied!<p>For a more complete answer, one that also illustrates input redirection, I'm posting my code. Thanks to David Heffernan for guidance, without which this would not be possible.</p> <p>The code involves backup and restore of a SQLite database, by calling the Sqlite3.exe executable file using CreateProcess. Obviously input and output needs to be redirected to/from this command and the code below illustrates how to achieve this:</p> <pre><code>function StartProcessWithRedirectedOutput(const ACommandLine: string; const AOutputFile: string; AShowWindow: boolean = True; AWaitForFinish: boolean = False): Integer; var CommandLine: string; StartupInfo: TStartupInfo; ProcessInformation: TProcessInformation; StdOutFileHandle: THandle; begin Result := 0; StdOutFileHandle := CreateFile(PChar(AOutputFile), GENERIC_WRITE, FILE_SHARE_READ, nil, CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL, 0); Win32Check(StdOutFileHandle <> INVALID_HANDLE_VALUE); try Win32Check(SetHandleInformation(StdOutFileHandle, HANDLE_FLAG_INHERIT, 1)); FillChar(StartupInfo, SizeOf(TStartupInfo), 0); FillChar(ProcessInformation, SizeOf(TProcessInformation), 0); StartupInfo.cb := SizeOf(TStartupInfo); StartupInfo.dwFlags := StartupInfo.dwFlags or STARTF_USESTDHANDLES; StartupInfo.hStdInput := GetStdHandle(STD_INPUT_HANDLE); StartupInfo.hStdOutput := StdOutFileHandle; StartupInfo.hStdError := StdOutFileHandle; if not(AShowWindow) then begin StartupInfo.dwFlags := StartupInfo.dwFlags or STARTF_USESHOWWINDOW; StartupInfo.wShowWindow := SW_HIDE; end; CommandLine := ACommandLine; UniqueString(CommandLine); Win32Check(CreateProcess(nil, PChar(CommandLine), nil, nil, True, CREATE_NEW_PROCESS_GROUP + NORMAL_PRIORITY_CLASS, nil, nil, StartupInfo, ProcessInformation)); try Result := ProcessInformation.dwProcessId; if AWaitForFinish then WaitForSingleObject(ProcessInformation.hProcess, INFINITE); finally CloseHandle(ProcessInformation.hProcess); CloseHandle(ProcessInformation.hThread); end; finally CloseHandle(StdOutFileHandle); end; end; function StartProcessWithRedirectedInput(const ACommandLine: string; const AInputFile: string; AShowWindow: boolean = True; AWaitForFinish: boolean = False): Integer; var CommandLine: string; StartupInfo: TStartupInfo; ProcessInformation: TProcessInformation; StdInFileHandle: THandle; begin Result := 0; StdInFileHandle := CreateFile(PChar(AInputFile), GENERIC_READ, FILE_SHARE_READ, nil, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, 0); Win32Check(StdInFileHandle <> INVALID_HANDLE_VALUE); try Win32Check(SetHandleInformation(StdInFileHandle, HANDLE_FLAG_INHERIT, 1)); FillChar(StartupInfo, SizeOf(TStartupInfo), 0); FillChar(ProcessInformation, SizeOf(TProcessInformation), 0); StartupInfo.cb := SizeOf(TStartupInfo); StartupInfo.dwFlags := StartupInfo.dwFlags or STARTF_USESTDHANDLES; StartupInfo.hStdInput := StdInFileHandle; StartupInfo.hStdOutput := GetStdHandle(STD_OUTPUT_HANDLE); StartupInfo.hStdError := GetStdHandle(STD_OUTPUT_HANDLE); if not(AShowWindow) then begin StartupInfo.dwFlags := StartupInfo.dwFlags or STARTF_USESHOWWINDOW; StartupInfo.wShowWindow := SW_HIDE; end; CommandLine := ACommandLine; UniqueString(CommandLine); Win32Check(CreateProcess(nil, PChar(CommandLine), nil, nil, True, CREATE_NEW_PROCESS_GROUP + NORMAL_PRIORITY_CLASS, nil, nil, StartupInfo, ProcessInformation)); try Result := ProcessInformation.dwProcessId; if AWaitForFinish then WaitForSingleObject(ProcessInformation.hProcess, INFINITE); finally CloseHandle(ProcessInformation.hProcess); CloseHandle(ProcessInformation.hThread); end; finally CloseHandle(StdInFileHandle); end; end; procedure TfAdmin.DoDBBackup(ADBBackupFile: String); var b, p, q: String; begin b := ExtractFilePath(ParamStr(0)) + 'PPDB.bak'; p := '"' + ExtractFilePath(ParamStr(0)) + 'sqlite3.exe"'; q := '"' + ExtractFilePath(ParamStr(0)) + 'PPDB.db" .dump'; fMain.UniConnection1.Close; try StartProcessWithRedirectedOutput(p + ' ' + q, b, True, True); finally fMain.UniConnection1.Open; end; ZipMaster1.FSpecArgs.Add(b); ZipMaster1.ZipFileName := ADBBackupFile; ZipMaster1.Add; DeleteFile(b); ShowMessage('Backup complete!'); end; procedure TfAdmin.DoDBRestore(ADBBackupFile: String); var b, p, q, q2, r: String; begin b := ExtractFilePath(ParamStr(0)) + 'PPDB.bak'; p := '"' + ExtractFilePath(ParamStr(0)) + 'sqlite3.exe"'; q := '"' + ExtractFilePath(ParamStr(0)) + 'PPDB.db"'; ZipMaster1.ExtrBaseDir := ExtractFilePath(ParamStr(0)); ZipMaster1.ExtrOptions := [ExtrOverWrite]; ZipMaster1.ZipFileName := ADBBackupFile; ZipMaster1.Extract; fMain.UniConnection1.Close; try q2 := StringReplace(q, '"', '', [rfReplaceAll]); r := ChangeFileExt(q2, '.db$'); if FileExists(r) then DeleteFile(r); if not RenameFile(q2, r) then RaiseLastOSError; StartProcessWithRedirectedInput(p + ' ' + q, b, True, True); finally fMain.UniConnection1.Open; end; DeleteFile(b); ShowMessage('Restore complete!'); end; </code></pre>

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