Script is ok on perl command line but datasource output :0

[fairydream]

I have a data input method script to get current calls and the graph is ok with cacti 0.8.7a on windows host.
//------------------------------------------
#!/usr/bin/perl -w
@lists=`snmpwalk -Ov -v 2c -c snmp_str 10.84.10.29 1.3.6.1.4.1.9.9.63.1.3.2.1.25`;
$calls = @lists/2;
$test=400;
print $calls;
//----------------------------------------------
On linux host with cacti 0.8.6h, althought output value is returned when run perl command line, the cacti graph value is NaN.

[root@nms-cacti /]# perl var/www/html/cacti/scripts/ipgwcall2.pl
45[root@nms-cacti /]#

in Cacti log shows Output :0
04/02/2008 03:45:02 PM - CACTID: Poller[0] Host[0] DS[659] SCRIPT: perl /var/www/html/cacti/scripts/ipgwcall2.pl, output: 0

I misunderstand because if i replace $calls by a contant value $test , datasource output is 400 and the graph shows this value (400)

Something is wrong with my script or Cacti ? Need someone help me !

[TheWitness]

Use snmpget instead of snmpwalk, and then don't use an array.

TheWitness

[TheWitness]

I also suggest that you simply use the snmp functions in cacti instead of perl, as it's much faster and then use a cdef to do the division.

TheWitness

[fairydream]

Thank you !
But I think the problem is snmpwalk(or snmpget) don't run when cacti poller calls script, so no output value return.
Have output return in perl command line, and everything' s ok with cacti 0.87a installed in windows host (output value, graph shows)
But It crazy in linux ! I'm a linux newbie.