Hi, I'm new to Perl, i have a script like this : 
#!/usr/bin/perl -w
use strict;

my @word = qw(xxx yyy zzz);
open(PF,"|grep xxx") or die "failed \n";
foreach(@word) {
  print "here \n";
  print PF $_;
}
print "going to close filehandle\n";
close(PF) or die "failed\n";
print "here 2\n";

[download]

I thought i'll get 'xxx' but that's not what i've got. Then i changed print PF $_; to print PF "$_ \n"; and i got the result that i expect.

But i can't explain the real different of these 2 codes to my self.

And i need your help.

It's looks when close(PF) eq to echo xxxyyyzzz |grep xxx.

Thank you

In reply to Pipe, when this shell command is going to executed ? by Anonymous Monk

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