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From: "Mark Delany" <n7w@delta.emu.st>
To: freebsd-hackers@freebsd.org
Subject: Re: How to send EOF to the popen(3) pipe?
References: <5699BAC9.3060407@rawbw.com> <5699C8AB.7070006@missouri.edu>
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On 16Jan16, Yuri allegedly wrote:
> No, pclose kills the process and returns the exit code. Half-closed 
> connection though can be alive for a while, until the other side 
> finishes and closes the pipe.

> I think the answer to my question is "no". popen(3) can't send EOF. 
> Protocol needs to support EOF signal on the application-level.

Right.

Sounds like you need an fshutdown(FILE*, int how) that is analogous to
shutdown(2).

Unfortunately you can't hack it with:

    fflush(FILE*);
    shutdown(fileno(FILE*), SHUT_WR);

as shutdown() only works on sockets, not pipes.

I guess your best choice is to implement your own popen() with
socketpair() then you can shutdown() on it.


Mark.