10-16-2008
Quote:
Originally Posted by
shamrock
You're not capturing the return value of the dupPipe function in main() outlined in red. The newly created destfd is lost so you can't connect the two processes together.
I think I have figured it out. I am creating a new pipe for every process in the for -loop( not shown in the code).
I am not anymore.
Now I am able to do for example ls|wc. but I have to finish whit an Enter. I think it has to do whit not closed pipe ends in parent.
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LEARN ABOUT DEBIAN
io::pipe
IO::Pipe(3perl) Perl Programmers Reference Guide IO::Pipe(3perl)
NAME
IO::Pipe - supply object methods for pipes
SYNOPSIS
use IO::Pipe;
$pipe = IO::Pipe->new();
if($pid = fork()) { # Parent
$pipe->reader();
while(<$pipe>) {
...
}
}
elsif(defined $pid) { # Child
$pipe->writer();
print $pipe ...
}
or
$pipe = IO::Pipe->new();
$pipe->reader(qw(ls -l));
while(<$pipe>) {
...
}
DESCRIPTION
"IO::Pipe" provides an interface to creating pipes between processes.
CONSTRUCTOR
new ( [READER, WRITER] )
Creates an "IO::Pipe", which is a reference to a newly created symbol (see the "Symbol" package). "IO::Pipe::new" optionally takes two
arguments, which should be objects blessed into "IO::Handle", or a subclass thereof. These two objects will be used for the system call
to "pipe". If no arguments are given then method "handles" is called on the new "IO::Pipe" object.
These two handles are held in the array part of the GLOB until either "reader" or "writer" is called.
METHODS
reader ([ARGS])
The object is re-blessed into a sub-class of "IO::Handle", and becomes a handle at the reading end of the pipe. If "ARGS" are given
then "fork" is called and "ARGS" are passed to exec.
writer ([ARGS])
The object is re-blessed into a sub-class of "IO::Handle", and becomes a handle at the writing end of the pipe. If "ARGS" are given
then "fork" is called and "ARGS" are passed to exec.
handles ()
This method is called during construction by "IO::Pipe::new" on the newly created "IO::Pipe" object. It returns an array of two objects
blessed into "IO::Pipe::End", or a subclass thereof.
SEE ALSO
IO::Handle
AUTHOR
Graham Barr. Currently maintained by the Perl Porters. Please report all bugs to <perl5-porters@perl.org>.
COPYRIGHT
Copyright (c) 1996-8 Graham Barr <gbarr@pobox.com>. All rights reserved. This program is free software; you can redistribute it and/or
modify it under the same terms as Perl itself.
perl v5.14.2 2011-09-19 IO::Pipe(3perl)