C ++下的跨进程交互

Question

Please help, how can I organize the process-process data exchange (in Windows, if that matters)?

I have process1.exe which calls process2.exe with a few command line arguments. I want to track "progress" of process2 from process1 (say, some int value). It (that int value) can be accessed from process1 permanently or each X ms - doesn't matter.

Will be useful any solution: WinApi or Qt.

Thank you everybody! All answers are very useful! :) Many thanks!!

Answer 1

OTOH:

• stdin/stdout redirection
• Named pipe (CreateNamedPipe)
• Anonymous pipe (CreatePipe)
• Sockets (socket, connect, bind)
• Shared memory (CreateFileMapping, MapViewOfFile)
• Windows messages (eg WM_APP)

Pick one - Windows messages or shared memory may be the easier ones.

Answer 2

There are many options here:

1. You can redirect the standard output of process2 and have it output updates however often you like
2. If stdout is being used for something else, you can use a named pipe between the processes
3. You can also use named shared memory , which will require less overhead and probably be easier to implement (the downside is that you may need to also do cross-process synchronization)
4. If process1 is running a message pump, then you can also use normal Windows messages (look at WM_COPYDATA)

Answer 3

There are several methods:

• Sockets
• Messages
• Shared Memory (files)

The issue is that Process2 will be broadcasting and Process1 will be listening. Process1 will need to know when Process2 is finished and maybe the percentage complete.

I believe Sockets would be the better route, but that depends on the application, development schedule and familiarity of concepts.

Answer 4

您只需使用Windows Api（SendMessage）发送消息即可。

Answer 5

An obvious omission in the options presented so far is COM. I'm expecting the usual flurry of "COM is crap" responses, but in my experience this hasn't been the case.