This is the mail archive of the cygwin mailing list for the Cygwin project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

Re: Replacing fork/exec with spawn question


On Sun, Nov 25, 2012 at 12:13:59PM -0500, LMH wrote:
>It may be better to move such a discussion to a programing board since 
>some of this will not relate to cygwin and it would be nice to have 
>things like php formatted code, attachments, etc. The mods here can let 
>us know about that. I have thought at times that some of the code I have 
>here should be made into some kind of IPC API. Perhaps others would find 
>that useful.

As a "mod" I can safely say that any topic which discusses how not to
use Cygwin can safely be considered to be off-topic.

However, if you're talking about Cygwin's version of spawn which is (IMO
misguidedly) intended to mimic the spawn* functions in Windows then, if
you are trying to use pipes, you will probably need to investigate how
to use close-on-exec to close one side of the pipe while passing the
other to the subprocess.  You should be able to play games with fds
using dup2, dup, and close-on-exec to force a pipe to be the stdin or
stdout of a subprocess.  It would be tricky but doable.

http://pubs.opengroup.org/onlinepubs/009695399/functions/fcntl.html
http://pubs.opengroup.org/onlinepubs/009695399/functions/dup2.html
http://msdn.microsoft.com/en-US/library/20y988d2%28v=vs.80%29.aspx

--
Problem reports:       http://cygwin.com/problems.html
FAQ:                   http://cygwin.com/faq/
Documentation:         http://cygwin.com/docs.html
Unsubscribe info:      http://cygwin.com/ml/#unsubscribe-simple


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]