LinuxQuestions.org - get a status output

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- - get a status output (https://www.linuxquestions.org/questions/programming-9/get-a-status-output-347256/)

get a status output

hi

I've this perl script:

Code:

#!/usr/bin/perl -w



use strict;

use warnings;

use CGI;

my $query = new CGI;

use CGI::Carp qw(fatalsToBrowser);

my $process = "ntop";



print $query->header;

print "<html>\n";

print "<head>\n";

print "<title>stop ntop</title>\n";

print "</head>\n";

print "<body bgcolor='#c0c0d0'>\n";

print "<center>";



my $return = 'ps -eaf |grep $process |grep -v grep';



my $stop = '/usr/local/bin/sudo /usr/local/www/cgi-bin/ntop/ntop.sh stop &';

system ($stop) or die "... ";



if ($stop == -1) {

    print "failed to execute: $!\n";

} elsif ($stop & 127) {

    printf "ntop died with signal %d, %s coredump\n",

        ($stop & 127),  ($stop & 128) ? 'with' : 'without';

} else {

    printf "ntop exited with value %d\n", $stop >> 8;

}



print "<font face=\"arial,helvetica\" size=2 color=\"#006600\">status:</font> ",$stop,"<br><br>\n";

print "</center>";

print "</body>";

print "</html>";

howto change it to get the output status in the browser:

"ntop is not running"

or

"ntop was killed"

kind regards
cccc

At what point do you want it to display that?

for example:

ntop was killed with...

or

ntop exited with value...

Isn't that already in there?

No, I get:

Code:

Software error:



...  at /usr/local/www/cgi-bin/ntop/bb.cgi line 21.

And you didn't think to mention that in your original question?

Does it really just show ..., or is there more detail?

no, you're completely right !

I'm looking for a output solution, if I have like in my first or like in the second question,
I'll be happy.

greetings
cccc

Ah, wait, I see, you intentionall just output "...". Nice error message. Very microsoftesque. :)

You need to (I think) remove the & from the end of your my $stop = ... line.

I changed to:

Code:

my $return = 'ps -eaf |grep $process |grep -v grep';



my $stop = '/usr/local/bin/sudo /usr/local/www/cgi-bin/ntop/ntop.sh stop';

system ($stop) or die "cannot stop ntop: $!";



if ($stop == -1) {

    print "failed to execute: $!\n";

} elsif ($stop & 127) {

    printf "ntop died with signal %d, %s coredump\n",

        ($stop & 127),  ($stop & 128) ? 'with' : 'without';

} else {

    printf "ntop exited with value %d\n", $stop >> 8;

}

but still get this error message.

If you use backquotes around the cmd instead of single quotes, you'll get the returned text in $stop.

Backquotes are little bit dangerous
The expression within the backticks is executed upon assignment, and the $stop variable will hold the output of the expression.
Later, when I try to use
system($stop)
it would try to execute all that mess the ntop.sh program printed out.
I cannot take the output of ntop, and feed it back to system!

Then don't execute it through system(). Your system() call is failing, obviously.

Yes, you're completely right.

but how can I stop in other way ?

or is it:

Code:

system '/usr/local/bin/sudo /usr/local/www/cgi-bin/ntop/ntop.sh stop' and die "... ";

a solution ?