in reply to Screen Output Buffering

I'm surprised this hasn't been answered already. STDOUT in perl is buffered by default. To make sure STDOUT is autoflushed, set $| to a true value early in your program. STDOUT is not buffered by default.

If another file handle has been selected, you may need to select STDOUT before setting $|.

See perldoc perlfun and perldoc perlvar fore more information on flushing and $|.

hth,

Kyle

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Re^2: Screen Output Buffering
by Limbic~Region (Chancellor) on Aug 19, 2004 at 21:39 UTC
    mortis,
    To make sure STDOUT is autoflushed, set $| to a true value early in your program

    I am sorry about nitpicking but setting $| to a true value will turn on auto-flushing for the currently selected file handle. I know it is being pedantic, but just because STDOUT is the default selected file handle doesn't mean it has to be: 

    #!/usr/bin/perl
use strict;
use warnings;

open (FILE, '>', 'foo.txt') or die "Unable to open foo.txt for writing
+ : $!";
select FILE;
$| = 1;                               # FILE is now unbuffered
print "hello, world\n";

print STDOUT "goodbye cruel world\n"; # still buffered

    [download]

    Cheers - L~R

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Re^2: Screen Output Buffering
by mvaline (Friar) on Aug 19, 2004 at 21:12 UTC
    Thanks! That worked. I guess I didn't grep perlfun and perldoc accurately enough. I appreciate the help.
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