in reply to Newbie: Pipe/STDIN Clarification

You don't need to touch STDOUT actually, and you can simplify the file read:
my $stringified = '';
{
#Go into local slurp mode ..
local $/=undef;
open FH, "< ./demo.mail";
$stringified = <FH>;
close FH;


open (CMD_OUT, "/usr/lib/dovecot/deliver -f 
+test\@somedomain.com -d test\@mailtask.dom $stringified"|);
my $test = <CMD_OUT>;
print $test;
close CMD_OUT;
}

[download]


The 'local $/=undef' bit turns off the normal record separator (newline by default). So when the filehandle is read the data is slurped in as one record. The point of enclosing in {}'s is to localise the effect - outside the {}'s the default separator will be used.

You could also use the back-tick notation to run the shell command: 
my $test = `/usr/lib/dovecot/deliver -f 
+test\@somedomain.com -d test\@mailtask.dom $stringified`;

[download]
There are other ways of course. This is perl after all.

Replies are listed 'Best First'.
Re^2: Newbie: Pipe/STDIN Clarification
by graff (Chancellor) on Nov 05, 2011 at 13:57 UTC
    Two problems: (1) your "local slurp" isn't local enough, and (2) I think you misread the OP's intention -- mpapet wants to write to the "deliver" process, not read from it. (And BTW, you should indent, and be careful about how line-wrapping in code blocks is handled here at PM.) 
    my $stringified;
{
    local $/;  # defaults to undef
    open my $fh, '<', './demo.mail';  # 3-arg open is nice
    $stringified = <$fh>;
}
# input's done, end-of-block closes the file and reverts to normal i/o

my @cmd = qw(
     /usr/lib/dovecot/deliver
     -f test@somedomain.com
     -d test@mailtask.dom );

open( CMD_OUT, '|-', @cmd ) or die $!;
print CMD_OUT $stringified;
close CMD_OUT;

    [download]
    (Updated to use lexically-scoped file handle in the localized input block -- that's what will cause the file to be closed on leaving the block.)
[reply]
[d/l]
      Ah - but as you say I misread the OP's intention. The localised slurp also encompassed the (incorrectly) assumed read from the command - which I assumed would come with line feeds.

      Thanks for the tip on indents.
[reply]
Re^2: Newbie: Pipe/STDIN Clarification
by mpapet (Novice) on Nov 05, 2011 at 13:54 UTC
    Thanks for both replies.

    If I try to pass the contents of the variable, it errors out. "Fatal: Unknown argument: From" That's the first line of my demo.mail file. I think it's safe to assume it is reading the string as a file name only.

    That means one more step of writing the email out to disk using the lda program as-is.

[reply]
      It's unfortunate that the first two replies to your OP (from Anonymous Monk and mrstlee) were wrong, and/or didn't quite get your question. Of course there's no guarantee that my replies are correct, either...
[reply]

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