Greetings, honorable monks...
I come today to seek your wisdom...

I wrote a package from which a sub named '_runReadWrite' can be called to run processes on the server. After searching for the best solution, I finally chose to implement it using IPC::Open3, in a basic way that was taken from the Camel book:

# declare needed variables and connect to process
local (*CHILD_IN, *CHILD_OUT, *CHILD_ERR);
my ($childpid, @outlines, @errlines);
$childpid = open3(*CHILD_IN, *CHILD_OUT, *CHILD_ERR, $cmd);

# feed input to process, then close input
print CHILD_IN $input; close (CHILD_IN);

# save output and errors, close channels and process
chomp(@outlines = <CHILD_OUT>); close (CHILD_OUT);
chomp(@errlines = <CHILD_ERR>); close (CHILD_ERR);
waitpid($childpid, 0);

# return the result of the call
return { OUTPUT => \@outlines , ERRORS => \@errlines };

[download]
Until today, any call to this sub worked perfectly. But unfortunately, things have changed...

The problem is that I now have a script that has, at some point, to close STDOUT, in order to unhook a child fork from the browser in a CGI script.

Now, later in that process, I make a call to my '_runReadWrite' function, which lamentably fails capturing the launched process' output.

What I would like to do, in the sub that runs open3, is to add some branching and/or additional tests so it still works when STDOUT is closed in the calling process. In other words, I would like it to continue working as it did so far when STDOUT is open, but use another way when that channel is closed. I have tried many things, searched for answers everywhere, but I did not manage to find a complete solution so far, and this is why I today address your wisdom...

Can anyone help me (and maybe others) with this ?
A proud initiate :)

In reply to IPC::Open3 & closed STDOUT by lgauthie

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