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From: efoss on 2 Mar 2010 13:44
I want to be certain that a print statement is immediately executed.
Googling around led me to use "$| = 1". Is this correct? Here is an
example of how I'm using it:

my $test;

$| = 1;

$test = 3;

print "test is $test\n";

Thanks.

Eric
From: J�rgen Exner on 2 Mar 2010 13:50
"efoss(a)fhcrc.org" <efoss(a)fhcrc.org> wrote:
>I want to be certain that a print statement is immediately executed.
>Googling around led me to use "$| = 1". Is this correct? Here is an
>example of how I'm using it:
>
>$| = 1;
>$test = 3;
>print "test is $test\n";

Yes, that is the correct use of $|.
However it only tells perl to not buffer the output and has no impact on
whatever buffereing your OS or terminal server or server-client protocol
(if applicable) decides to do.

jue
From: Ben Morrow on 2 Mar 2010 14:01

Quoth "efoss(a)fhcrc.org" <efoss(a)fhcrc.org>:
> I want to be certain that a print statement is immediately executed.
> Googling around led me to use "$| = 1". Is this correct? Here is an
> example of how I'm using it:

perldoc perlvar

Ben

From: Uri Guttman on 2 Mar 2010 14:29
>>>>> "JE" == J�rgen Exner <jurgenex(a)hotmail.com> writes:

JE> "efoss(a)fhcrc.org" <efoss(a)fhcrc.org> wrote:
>> I want to be certain that a print statement is immediately executed.
>> Googling around led me to use "$| = 1". Is this correct? Here is an
>> example of how I'm using it:
>>
>> $| = 1;
>> $test = 3;
>> print "test is $test\n";

JE> Yes, that is the correct use of $|.

actually that never uses $| ! the print string ends in newline so it
will always be flushed to stdout. $| is meant for when you print text
without a newline (say a prompt or partial output or to a socket).

also since the program ends there, you also won't see any difference
with setting $| or not as stdout gets flushed then as well. you need to
print a string without a newline and then sleep or wait for input or
something to see the difference.

uri

--
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From: Willem on 2 Mar 2010 15:41
Uri Guttman wrote:
) actually that never uses $| ! the print string ends in newline so it
) will always be flushed to stdout. $| is meant for when you print text
) without a newline (say a prompt or partial output or to a socket).
)
) also since the program ends there, you also won't see any difference
) with setting $| or not as stdout gets flushed then as well. you need to
) print a string without a newline and then sleep or wait for input or
) something to see the difference.

AFAIK, not true if stdout is redirected to a file.


SaSW, Willem
--
Disclaimer: I am in no way responsible for any of the statements
made in the above text. For all I know I might be
drugged or something..
No I'm not paranoid. You all think I'm paranoid, don't you !
#EOT
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