Re: Updating $r-connection-aborted before $r-print() ?
Geoffrey Young wrote:
yes, it worked for me. actually, I guess I should have been clearer - this
has nothing to do with $c-aborted or $r-print (well, on the outside
anyway). for $c-aborted you have to wait for Apache to flush the print
buffers. actually, in my tests $r-rflush didn't help things behave - only
$|=1 did.
Hey Geoff, for efficiency, my final code for detecting a client abort is:
sub Apache::ASP::Response::IsClientConnected {
...
# IsClientConnected ? Might already be disconnected for busy site, if
# a user hits stop/reload
my $conn = $self-{r}-connection;
my $is_connected = $conn-aborted ? 0 : 1;
if($is_connected) {
my $fileno = $conn-fileno;
if(defined $fileno) {
my $s = IO::Select-new($fileno);
$is_connected = $s-can_read(0) ? 0 : 1;
}
}
where $self is the ASP object ... I looked at the IO::Select-new()
and it looked pretty hairy, so I checked connection-aborted
status first in case it was already set.
-- Josh
_
Joshua Chamas Chamas Enterprises Inc.
NodeWorks Founder Huntington Beach, CA USA
http://www.nodeworks.com1-714-625-4051
RE: Updating $r-connection-aborted before $r-print() ?
Hey Geoff, for efficiency, my final code for detecting a client abort is: [snip] where $self is the ASP object ... I looked at the IO::Select-new() and it looked pretty hairy, so I checked connection-aborted status first in case it was already set. good idea. thanks for following up... --Geoff
RE: Updating $r-connection-aborted before $r-print() ?
On Sat, 15 Sep 2001, Geoffrey Young wrote:
my $fileno = $r-connection-fileno;
$s = IO::Select-new($fileno);
die aborted if grep { m/$fileno/ } $s-can_read(1);
Hmm, does this actually work Geoff? What happens if mod_perl is running
as a back-end? In this case $r-connection-aborted doesn't work even if
you print.
yes, it worked for me. actually, I guess I should have been clearer - this
has nothing to do with $c-aborted or $r-print (well, on the outside
anyway). for $c-aborted you have to wait for Apache to flush the print
buffers. actually, in my tests $r-rflush didn't help things behave - only
$|=1 did.
$s-can_read should always work because Apache marks the client output file
descriptor with a zero-length packet for reading when the client dies. so,
when you can read from where you ought to be writing, you can assume a
broken connection.
at least this is my understanding. wish I could take credit, though - Eric
discovered/documented this one a while ago:)
cool! Somehow I've missed this patch.
at any rate, this worked for me just fine in some tests, but I never tested
it against a front-end/back-end setup. seems like you would never be able
to detect a broken client connection from in a proxy setup anyway, but
that's not my area to comment on...
I'll give it a run when I get some time to play with it and update the
guide appropriately.
Thanks Geoff!
_
Stas Bekman JAm_pH -- Just Another mod_perl Hacker
http://stason.org/ mod_perl Guide http://perl.apache.org/guide
mailto:[EMAIL PROTECTED] http://apachetoday.com http://eXtropia.com/
http://singlesheaven.com http://perl.apache.org http://perlmonth.com/
Re: Updating $r-connection-aborted before $r-print() ?
Geoffrey Young wrote:
my $fileno = $r-connection-fileno;
$s = IO::Select-new($fileno);
die aborted if grep { m/$fileno/ } $s-can_read(1);
HTH
Thanks for this. The code that I ended up using for Apache::ASP was:
# IsClientConnected ? Might already be disconnected for busy site, if
# a user hits stop/reload
my $is_connected = 1;
my $fileno = $r-connection-fileno;
if(defined $fileno) {
my $s = IO::Select-new($fileno);
if($s-can_read(0)) {
$is_connected = 0;
}
}
The difference being the can_read(0) from can_read(1).
The 1 would create an unnecessary wait of 1 second I found,
whereas 0 does not, yet reports the aborted condition
accurately.
Thanks again!
-- Josh
_
Joshua Chamas Chamas Enterprises Inc.
NodeWorks Founder Huntington Beach, CA USA
http://www.nodeworks.com1-714-625-4051
Re: Updating $r-connection-aborted before $r-print() ?
Geoffrey Young wrote:
-Original Message-
From: Joshua Chamas [mailto:[EMAIL PROTECTED]]
Sent: Friday, September 14, 2001 3:21 PM
To: Mod Perl
Subject: Updating $r-connection-aborted before $r-print() ?
Hey,
In my own experience it seems that I can only get
$r-connection-aborted updated if I first do a $r-print().
Is there any way to get aborted to update without
$r-print?
my $fileno = $r-connection-fileno;
$s = IO::Select-new($fileno);
die aborted if grep { m/$fileno/ } $s-can_read(1);
Hmm, does this actually work Geoff? What happens if mod_perl is running
as a back-end? In this case $r-connection-aborted doesn't work even if
you print.
Joshua, what about print \0, I'm not sure whether this messes up the
headers. given that you end these tests with a new line.
_
Stas Bekman JAm_pH -- Just Another mod_perl Hacker
http://stason.org/ mod_perl Guide http://perl.apache.org/guide
mailto:[EMAIL PROTECTED] http://apachetoday.com http://eXtropia.com/
http://singlesheaven.com http://perl.apache.org http://perlmonth.com/
RE: Updating $r-connection-aborted before $r-print() ?
my $fileno = $r-connection-fileno;
$s = IO::Select-new($fileno);
die aborted if grep { m/$fileno/ } $s-can_read(1);
Hmm, does this actually work Geoff? What happens if mod_perl is running
as a back-end? In this case $r-connection-aborted doesn't work even if
you print.
yes, it worked for me. actually, I guess I should have been clearer - this
has nothing to do with $c-aborted or $r-print (well, on the outside
anyway). for $c-aborted you have to wait for Apache to flush the print
buffers. actually, in my tests $r-rflush didn't help things behave - only
$|=1 did.
$s-can_read should always work because Apache marks the client output file
descriptor with a zero-length packet for reading when the client dies. so,
when you can read from where you ought to be writing, you can assume a
broken connection.
at least this is my understanding. wish I could take credit, though - Eric
discovered/documented this one a while ago:)
at any rate, this worked for me just fine in some tests, but I never tested
it against a front-end/back-end setup. seems like you would never be able
to detect a broken client connection from in a proxy setup anyway, but
that's not my area to comment on...
--Geoff
Updating $r-connection-aborted before $r-print() ?
Hey, In my own experience it seems that I can only get $r-connection-aborted updated if I first do a $r-print(). Is there any way to get aborted to update without $r-print? The scenario is that developer would like to know the aborted status before any part of the script runs, where browser requests might queue up on a busy server for 3+ seconds before the scripts run, hit the STOP button reload. Unfortunately, to have to print() or send headers before an aborted check means that the headers have already been sent out, which is limiting. Thanks, Josh _ Joshua Chamas Chamas Enterprises Inc. NodeWorks Founder Huntington Beach, CA USA http://www.nodeworks.com1-714-625-4051
RE: Updating $r-connection-aborted before $r-print() ?
-Original Message-
From: Joshua Chamas [mailto:[EMAIL PROTECTED]]
Sent: Friday, September 14, 2001 3:21 PM
To: Mod Perl
Subject: Updating $r-connection-aborted before $r-print() ?
Hey,
In my own experience it seems that I can only get
$r-connection-aborted updated if I first do a $r-print().
Is there any way to get aborted to update without
$r-print?
my $fileno = $r-connection-fileno;
$s = IO::Select-new($fileno);
die aborted if grep { m/$fileno/ } $s-can_read(1);
HTH
--Geoff
