The ^E is the same whether the pipe opens or not. Same problems with IPC::Open2 and IO::Pipe.
Back ticks usually work but in this case the program may return 10's or 100's of MB and I'm short on resources. I found a work around by doing this. open(PIPE, "hostname |"); die "Pipe didn't open or it returned nothing" if (eof(PIPE)); -----Original Message----- From: $Bill Luebkert [mailto:dbec...@roadrunner.com] Sent: Sunday, August 12, 2012 6:35 PM To: Edwards, Mark (CXO) Cc: activeperl@listserv.activestate.com Subject: Re: Testing Success of Opening Pipe in Windows On 8/12/2012 13:48, Edwards, Mark (CXO) wrote: > The typical test for open is ... > > open(HANDLE, "something _/to/_open") or die "Open failed, $!"; > > That works on Windows for a file but not a pipe. > > $status=open(PIPE, "hostname |"); > > This works and I can read from the pipe but $status is always non-zero so I > don't know whether it succeeds or fails. Even testing for $! or $? doesn't > work. $? is always -1 and $! is always " Inappropriate I/O control > operation". This works as expected on Unix be how do I test for success or > failure of opening the pipe? Any reason why not to just use a backtick version: my $host = `hostname`; chomp $host; print "OS Error: '$!'\n"; print "Child Error: '$?'\n"; print "^E : '$^E'\n"; print "Host Name: '$host'\n"; OS Error: '' Child Error: '0' ^E : 'The pipe has been ended' Host Name: 'MYHOST' or use IO::Pipe; my $pipe = new IO::Pipe; $pipe->reader('hostname'); my $host; { local $/ = undef; $host = <$pipe> } my $status = $pipe->close; print "OS Error: '$!'\n"; print "Child Error: '$?'\n"; print "^E : '$^E'\n"; print "Status: $status\n"; print "Host Name: $host\n"; print "\n"; OS Error: '' Child Error: '0' ^E : 'The pipe has been ended' Status: 1 Host Name: MYHOST _______________________________________________ ActivePerl mailing list ActivePerl@listserv.ActiveState.com To unsubscribe: http://listserv.ActiveState.com/mailman/mysubs
