Only for novice monks too lazy to read dominus's suffering from buffering:
from perlvar:
HANDLE->autoflush(EXPR)
$OUTPUT_AUTOFLUSH # need to use English at the start of your module
$|
If set to nonzero, forces a flush right away and after every write
+ or print on the currently selected output channel. Default is 0 (reg
+ardless of whether the channel is really buffered by the system or no
+t; $| tells you only whether you've asked Perl explicitly to flush af
+ter each write). STDOUT will typically be line buffered if output is
+to the terminal and block buffered otherwise. Setting this variable i
+s useful primarily when you are outputting to a pipe or socket, such
+as when you are running a Perl program under rsh and want to see the
+output as it's happening. This has no effect on input buffering. See
+getc in the perlfunc manpage for that. (Mnemonic: when you want your
+pipes to be piping hot.)
Some simple code:
#see also http://perl.plover.com/FAQs/Buffering.html
use strict;
use warnings;
#prints, waits a second, prints
for (1..3) {
sleep 1;
print "$_\n";
}
#without the newline, waits the entire time and then prints the whole
+thing.
for (1..3) {
sleep 1;
print "$_";
}
$| = 1;
#now it works
for (1..3) {
sleep 1;
print "$_";
}
#you might want to go back to the default behavior now.
$| = 0;
Considered (dvergin): Author requests this be listed on Tutorials page. What say you all?
Unconsidered (holli): Enough Keep Votes (Keep/Edit/Delete: 20/21/1)
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