How can I get the output of a command terminated by a alarm() call in Perl?

Posted by rockyurock on Stack Overflow See other posts from Stack Overflow or by rockyurock
Published on 2010-04-02T16:37:22Z Indexed on 2010/04/03 4:53 UTC
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Filed under:

data

|

perl

|

windows-services

Case 1

If I run below command i.e iperf in UL only, then i am able to capture the o/p in txt file

@output = readpipe("iperf.exe -u -c 127.0.0.1 -p 5001 -b 3600k -t 10 -i 1");
open FILE, ">Misplay_DL.txt" or die $!;
print FILE @output;
close FILE;

Case 2

When I run iperf in DL mode , as we know server will start listening in cont. mode like below even after getting data from client (Here i am using server and client on LAN)

@output = system("iperf.exe -u -s -p 5001 -i 1");

on server side:

D:\_IOT_SESSION_RELATED\SEEM_ELEMESNTS_AT_COMM_PORT_CONF\Tput_Related_Tools\AUTO
MATION_APP_\AUTOMATION_UTILITY>iperf.exe -u -s -p 5001
------------------------------------------------------------
Server listening on UDP port 5001
Receiving 1470 byte datagrams
UDP buffer size: 8.00 KByte (default)
------------------------------------------------------------
[1896] local 192.168.5.101 port 5001 connected with 192.168.5.101 port 4878
[ ID] Interval Transfer Bandwidth Jitter Lost/Total Datagrams
[1896] 0.0- 2.0 sec 881 KBytes 3.58 Mbits/sec 0.000 ms 0/ 614 (0%)

command prompt does not appear , process is contd...

on client side:

D:\_IOT_SESSION_RELATED\SEEM_ELEMESNTS_AT_COMM_PORT_CONF\Tput_Related_Tools\AUTO
MATION_APP_\AUTOMATION_UTILITY>iperf.exe -u -c 192.168.5.101 -p 5001 -b 3600k -t
2 -i 1
------------------------------------------------------------
Client connecting to 192.168.5.101, UDP port 5001
Sending 1470 byte datagrams
UDP buffer size: 8.00 KByte (default)
------------------------------------------------------------
[1880] local 192.168.5.101 port 4878 connected with 192.168.5.101 port 5001
[ ID] Interval Transfer Bandwidth
[1880] 0.0- 1.0 sec 441 KBytes 3.61 Mbits/sec
[1880] 1.0- 2.0 sec 439 KBytes 3.60 Mbits/sec
[1880] 0.0- 2.0 sec 881 KBytes 3.58 Mbits/sec
[1880] Server Report:
[1880] 0.0- 2.0 sec 881 KBytes 3.58 Mbits/sec 0.000 ms 0/ 614 (0%)
[1880] Sent 614 datagrams

D:\_IOT_SESSION_RELATED\SEEM_ELEMESNTS_AT_COMM_PORT_CONF\Tput_Related_Tools\AUTO
MATION_APP_\AUTOMATION_UTILITY>

so with this as server is cont. listening and never terminates so can't take output of server side to a txt file as it is going to the next command itself to create a txt file

so i adopted the alarm() function to terminate the server side (iperf.exe -u -s -p 5001) commands after it received all data from the client.

could anybody suggest me the way..

Here is my code:

#! /usr/bin/perl -w
my $command = "iperf.exe -u -s -p 5001";
my @output;
eval {
    local $SIG{ALRM} = sub { die "Timeout\n" };
    alarm 20;
    #@output = `$command`;
#my @output = readpipe("iperf.exe -u -s -p 5001");
#my @output = exec("iperf.exe -u -s -p 5001");

my @output = system("iperf.exe -u -s -p 5001");
    alarm 0;
};
if ($@) {
    warn "$command timed out.\n";
} else {
    print "$command successful. Output was:\n", @output;
}
open FILE, ">display.txt" or die $!;
print FILE @output_1;
close FILE;

i know that with system command i cannot capture the o/p to a txt file but i tried with readpipe() and exec() calls also but in vain...

could some one please take a look and let me know why the iperf.exe -u -s -p 5001 is not terminating even after the alarm call and to take the out put to a txt file

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