Re^2: Undestanding this code snippet

Thanks everyone for replying, you are right, there is a "|" as the file handle is opened...apologize that I missed that when I modified the command before posting :( (open F, "some_shell_expression |";)

With that said, is there still a way for catching that system error with the current code?
Thanks again!

Comment on Re^2: Undestanding this code snippet

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Re^3: Undestanding this code snippet by shmem (Chancellor) on Jul 21, 2008 at 20:17 UTC
Yes - see IPC::Open3. That module provides capturing STDERR of a command. The exit status is available after reaping the child with waitpid. Example (untested): `my $pid = open3('<&STDIN', \CHLD_OUT, \CHLD_ERR, "some_shell_express +ion"); while(<CHLD_OUT>) { # do something with that command's output } my $err = <CHLD_ERR>; # may block - better use select here waitpid $pid, 0; if ( $? ) { warn $_[0] . ($? == -1) ? "failed to execute: $!\n" : ($? & 127) ? sprintf "child died with signal %d, %s coredump\n", ($? & 127), ($? & 128) ? 'with' : 'without' : sprintf "child exited with value %d\n", $? >> 8; }` [download] --shmem _($_=" "x(1<<5)."?\n".q·/)Oo. G°\ / /\_¯/(q / ---------------------------- \__(m.====·.(_("always off the crowd"))."· ");sub _{s./.($e="'Itrs `mnsgdq Gdbj O`qkdq")=~y/"-y/#-z/;$e.e && print}	[reply] [d/l]

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Re^3: Undestanding this code snippet
by shmem (Chancellor) on Jul 21, 2008 at 20:17 UTC

Yes - see IPC::Open3. That module provides capturing STDERR of a command. The exit status is available after reaping the child with waitpid. Example (untested):

my $pid = open3('<&STDIN', \*CHLD_OUT, \*CHLD_ERR, "some_shell_express
+ion");
while(<CHLD_OUT>) {
    # do something with that command's output
}
my $err = <CHLD_ERR>; # may block - better use select here

waitpid $pid, 0;

if ( $? ) {
    warn $_[0]
    . ($? == -1) ? "failed to execute: $!\n"
    : ($? & 127) ? sprintf "child died with signal %d, %s coredump\n",
                ($? & 127),  ($? & 128) ? 'with' : 'without'
    : sprintf "child exited with value %d\n", $? >> 8;
}
[download]

--shmem

_($_=" "x(1<<5)."?\n".q·/)Oo.  G°\        /
                              /\_¯/(q    /
----------------------------  \__(m.====·.(_("always off the crowd"))."·
");sub _{s./.($e="'Itrs `mnsgdq Gdbj O`qkdq")=~y/"-y/#-z/;$e.e && print}

[reply]
[d/l]