列表6.9.txt

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【列表6.9】摘录自PipeChildMain.pas的程序代码。
const
 StrIndexLen = 4;
 LF = ^J; { ASCII linefeed/newline }
var
   PipeChildMainForm: TPipeChildMainForm;
   ParentReadPipe : Integer;
   SigActionRec : TSigAction;
 implementation
 {SR *.xfm}
 procedure Handler(Sig : Integer); cdecl;
 begin
   case Sig of
    SIGUSR1 : PipeChildMainForm. ReadPipe;
   end; { case }
 end;
  procedure InstallHandler;
with SigActionRec do
  begin
   sigaction_handler := Handler;
    sigemptyset(sa_mask);
    sa_flags :=0;
    sigaction(SIGUSR1, @SigActionRec, nil);
  end; { with }
end;
procedure TPipeChildMainForm. ReadPipe;
var
 ReadBuf : array[0..BUFSIZ] of Char;
 s : String;
  len : Integer;
begin
  { Get the length of the string }
  _read(ParentReadPipe, ReadBuf, StrIndexLen);
  ReadBuf[StrIndexLen] := chr(0);
  len := StrToInt(ReadBuf);
  { Get the string }
  read(ParentReadPipe, ReadBuf, len);
  ReadBuf[len] := chr(0);
  s := ReadBuf;
  MsgMemo,Lines.Add(s);
 end;
 procedure TPipeChildMainForm. FormCreate(Sender: TObject);
 begin
   InstallHandler;
   ParentReadPipe := StrToInt(ParamStr(1));
 end;