shahrahulb
asked on
perl cgi background process
i have a cgi script. problem is in that cgi script i m updating database...this takes approximately 2 minutes.
so the user has to wait 2 minutes when the browser is open which does not maks any sense.
can i do something like create a perl script (say background.pl) which does the updation of database.
when the user opens the cgi, the cgi should invoke the perl script but at the same time this script should be running in the background...so that the user in the foreground sees that everything is done...only thing is the perl application is running in background so that user does have to wait for 2 minutes to receive confoirmation...
as soon as user hits the submit button, he should immidiately get the confirmation
is it possible to do in cgi script.
so the user has to wait 2 minutes when the browser is open which does not maks any sense.
can i do something like create a perl script (say background.pl) which does the updation of database.
when the user opens the cgi, the cgi should invoke the perl script but at the same time this script should be running in the background...so that the user in the foreground sees that everything is done...only thing is the perl application is running in background so that user does have to wait for 2 minutes to receive confoirmation...
as soon as user hits the submit button, he should immidiately get the confirmation
is it possible to do in cgi script.
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ASKER
thx jhurst....i got it.
close(STDOUT) just before executing the system command
close(STDOUT) just before executing the system command
If you are running on MSwindows, system('cmd &') or fork may not work.
If you're running on Unix
close STDOUT; system('background.pl &');
could work.
or you could daemonise the child with
my $p=fork();
if( $p==0 ){
chdir '/' or die "Can't chdir to /: $!";
open STDIN, '/dev/null' or die "Can't read /dev/null: $!";
open STDOUT, '>/dev/null'
or die "Can't write to /dev/null: $!";
defined(my $pid = fork) or die "Can't fork: $!";
exit if $pid;
setsid or die "Can't start a new session: $!";
open STDERR, '>&STDOUT' or die "Can't dup stdout: $!";
do 'background.pl';
exit;
}
die "Can't fork $!" unless defined $p;
If you're running on Unix
close STDOUT; system('background.pl &');
could work.
or you could daemonise the child with
my $p=fork();
if( $p==0 ){
chdir '/' or die "Can't chdir to /: $!";
open STDIN, '/dev/null' or die "Can't read /dev/null: $!";
open STDOUT, '>/dev/null'
or die "Can't write to /dev/null: $!";
defined(my $pid = fork) or die "Can't fork: $!";
exit if $pid;
setsid or die "Can't start a new session: $!";
open STDERR, '>&STDOUT' or die "Can't dup stdout: $!";
do 'background.pl';
exit;
}
die "Can't fork $!" unless defined $p;
When I have had this I have just:
close(STDOUT);
and the web server has continued.
close(STDOUT);
and the web server has continued.
ASKER
as jhurst suggested, how do we close STDOUT
Rahul