perl getopt::long help

kdelover · 11-23-2009, 09:46 AM

hello all,

I am trying out the getopt::long perl module and i have a small problem with it

Code:

#!/usr/bin/perl
use strict   
use Getopt::Long;
my $data =;
my $length=;
my $verbose;
$result = GetOptions ("length=s" => \$length, # numeric
"file=s" => \$data, # string
"verbose" => \$verbose); # flag
print "$length,$file";

The problem is when i give the arguments as

Code:

./test --length --file "hello.txt"

Where the argument for --length is omitted,the value of variable length becomes --file

,is there anyway i can stop this from happening?

I need to implement optlong in one of my code,and if the user forgets to give a value for an option,i dont want the next option to become its value

. thanks

centosboy · 11-23-2009, 10:18 AM

Quote:

Originally Posted by kdelover

hello all,

I am trying out the getopt::long perl module and i have a small problem with it

Code:

#!/usr/bin/perl
use strict   
use Getopt::Long;
my $data =;
my $length=;
my $verbose;
$result = GetOptions ("length=s" => \$length, # numeric
"file=s" => \$data, # string
"verbose" => \$verbose); # flag
print "$length,$file";

The problem is when i give the arguments as

Code:

./test --length --file "hello.txt"

Where the argument for --length is omitted,the value of variable length becomes --file

,is there anyway i can stop this from happening?

I need to implement optlong in one of my code,and if the user forgets to give a value for an option,i dont want the next option to become its value

. thanks

you could add a condition to say if @ARGV is not equal to <number> return to help subrouting section. or if a number of arguments are not defined, then print correct syntax and exit.

Code:

if @ARGV != 3 
{
&help;
}

kdelover · 11-23-2009, 01:12 PM

Thanks,but the problem is if there are many options and the number of argumetns to take is not fixed,then it creates a problem.

MBybee · 11-23-2009, 01:56 PM

What I do is check for a "-" character at the start of the returned value. That way it'll choke if a switch gets passed as a value.

Telemachos · 11-23-2009, 02:27 PM

Check over the documentation for Getopt::Long a bit. You're defining --length in such a way that (1) an argument is required for it and (2) the argument is expected to be a string. Read over the section "Options with values".

If you haven't already, though, you might want to read over the entire "Getting started with Getopt::Long" section of the docs.