topic Re: Perl script - piping problem in Operating System - HP-UX

Perl script - piping problem

Piotr Kirklewski — Mon, 23 May 2011 01:40:02 GMT

Hi there

my @args = ( "ipcalc ", $net, "|","grep Wildcard" );
system (@args);

Why am i getting this:

ipcalc 2.1.2.0/20
|grep Wildcard

Rather then this:

ipcalc 2.1.2.0/20 |grep Wildcard

?

Re: Perl script - piping problem

Matti_Kurkela — Mon, 23 May 2011 04:30:47 GMT

Your $net variable probably contains a newline character at the end.

Use "chomp ($net);" to remove it.

MK

Re: Perl script - piping problem

Piotr Kirklewski — Mon, 23 May 2011 12:59:06 GMT

Yes it was the new line character. Thanks
Now what should I do to get rid of the error below ?

#!/usr/bin/perl

open (MYFILE,'/ip/a.txt');
while (){
$net = "$_"; #$net = "2.24.0.0/13"

chomp($net);
my @args = ( "ipcalc ", $net, "|","grep Wildcard|awk '{print \$2}' \>> /ip/b.txt" );
$cmd = @args[0].@args[1].@args[2].@args[3];
system ($cmd);
print "$cmd\n";
}
close (MYFILE);

Use of uninitialized value $ENV{"TERM"} in pattern match (m//) at /usr/bin/ipcalc line 714.
ipcalc 83.223.192.0/19|grep Wildcard|awk '{print $2}' >> /ip/b.txt

Re: Perl script - piping problem

James R. Ferguson — Mon, 23 May 2011 13:15:27 GMT

Hi:

> Now what should I do to get rid of the error below ?

Use of uninitialized value $ENV{"TERM"} in pattern match (m//) at /usr/bin/ipcalc line 714.
ipcalc 83.223.192.0/19|grep Wildcard|awk '{print $2}' >> /ip/b.txt

The environmental 'TERM' variable isn't set. Either set it before you run your script, or (better) test for "defined-ness" before referencing it. This will need to be done in '/ipcalc' --- the code for which you don't show.

Regards!

...JRF...

Re: Perl script - piping problem

Piotr Kirklewski — Mon, 23 May 2011 13:35:35 GMT

But ipcalc is a Liux utility.

Re: Perl script - piping problem

James R. Ferguson — Mon, 23 May 2011 13:59:24 GMT

Hi (again):

> But ipcalc is a Linux utility.

Then set the TERM variable to something in your script or on the command line!

# TERM=vt100 ./Piotr_Script

...Notice that there is whitespace after the setting without any semicolon before the run of your script. That sets the environmental variable only for the duration of your script.

Otherwise in your script do something like this shows:

# perl -le 'local $ENV{TERM}='vt100';print "[$ENV{TERM}]"'

Regards!

...JRF...

Re: Perl script - piping problem

James R. Ferguson — Mon, 23 May 2011 17:10:47 GMT

Piotr:

Did this solve your problem?

...JRF...

Re: Perl script - piping problem

Piotr Kirklewski — Mon, 23 May 2011 21:47:45 GMT

Yes
Thanks

Re: Perl script - piping problem

Piotr Kirklewski — Mon, 23 May 2011 22:40:20 GMT

One more question.
How do I get the output of $cmd to a perl variable.

$var = $cmd doesn't work.

#!/usr/bin/perl
system ("TERM=vt100");
local $ENV{TERM}='vt100';
#print "[$ENV{TERM}]"';
open (MYFILE,'/ip/a.txt');
while (){
$net = "$_"; #$net = "2.24.0.0/13"

chomp($net);
my @args = ( "ipcalc ", $net, "|","grep Wildcard|awk '{print \$2}' \>> /ip/b.txt" );
$cmd = @args[0].@args[1].@args[2].@args[3];
system ($cmd);
}
close (MYFILE);

Re: Perl script - piping problem

James R. Ferguson — Mon, 23 May 2011 22:53:17 GMT

Hi (again) Piotr:

> How do I get the output of $cmd to a perl variable.

The simplest way, when you don't care about the return code is to use backticks:

# perl -le '$result=`uname -a`;print $result'

If you dislike the backticks use 'qx( .... )':

# perl -le 'perl -le '$result=qx(uname -a);print $result'

Regards!

...JRF...

Re: Perl script - piping problem

Piotr Kirklewski — Mon, 23 May 2011 23:50:18 GMT

closed