perl assistance...

Ateo · 07-01-2005, 06:45 PM

I'm trying to grab 2 variables from this output:

Code:

dracco@death ~ $ iwconfig eth1 |grep "Link"
          Link Quality=83/100  Signal level=-47 dBm  Noise level=-82 dBm

I'm trying to get the link quality so I need the 83 and 100 as 2 separate variables. My perl book isn't helping. I'm confused as to how to parse a string and pick out strings within in that.... Any help would be appreciated....

keefaz · 07-01-2005, 07:02 PM

Is it a % value ? If yes 100 is a constant not a variable
I will assume it is a variable tough

Code:

open IWC, 'iwconfig eth1 |' or 
    die "Could not execute iwconfig eth1: $!\n";

while(<IWC>) {
    next unless /Link Quality/;
    my $s = $_;
    $s =~ s/.*=(\d+\/\d+).*/\1/;
    my($link, $total) = split /\//, $s;
}
close IWC;
print "Link Quality : $link\n";
print "total : $total\n";

Ateo · 07-01-2005, 07:08 PM

Didn't work..

Code:

dracco@death ~/.superkaramba/sysinfo/scripts $ ./link_quality.pl
Unmatched ( in regex; marked by <-- HERE in m/.*=( <-- HERE d+/ at ./link_quality.pl line 8.

It was a cut and paste job... so.. hmm.

keefaz · 07-01-2005, 07:13 PM

Please retry the copy and paste, I edited my post

Ateo · 07-01-2005, 07:34 PM

Still no.. hmm

Code:

dracco@death ~/.superkaramba/sysinfo/scripts $ ./link_quality.pl
\1 better written as $1 at ./link_quality.pl line 9.
Name "main::total" used only once: possible typo at ./link_quality.pl line 14.
Name "main::link" used only once: possible typo at ./link_quality.pl line 13.
Use of uninitialized value in concatenation (.) or string at ./link_quality.pl line 13.
Link Quality :
Use of uninitialized value in concatenation (.) or string at ./link_quality.pl line 14.
total :

aluser · 07-01-2005, 08:31 PM

perhaps

Code:

open IWC, 'iwconfig eth1 |' or 
    die "Could not execute iwconfig eth1: $!\n";
while (<IWC>) {
    if (/Link Quality=(\d+)\/(\d+)/) {
        my ($link, $total) = ($1, $2);
        print "link: $link, total: $total\n";
        last;
    }
}
close IWC;

that's untested also (lazy) but easier to read/debug perhaps...

keefaz: I think you've got a \1 where you want a $1 in the replacement part of s///

also, iwconfig might complain about "broken pipe" with my code. that's because it doesn't read (necessarily) all of the output from iwconfig. you can fix that if you like : )

Ateo · 07-02-2005, 12:42 PM

The last code did not work either...

Code:

dracco@death ~/.superkaramba/sysinfo/scripts $ ./link_quality.pl
\1 better written as $1 at ./link_quality.pl line 9.
Name "main::link" used only once: possible typo at ./link_quality.pl line 13.
Use of uninitialized value in concatenation (.) or string at ./link_quality.pl line 13.

aluser · 07-02-2005, 12:47 PM

that error is not for the snippet I posted.

Ateo · 07-02-2005, 08:07 PM

You were correct. My apologies. Your last code worked perfect. My gratitude.

Thanks!