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Help needed with if..exists in hash in perl

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# 1  
Old 05-29-2012
Help needed with if..exists in hash in perl
Hi,

So I have a hash,

Code:
%users = ("abc1" => "John Doe",
                 "xyz2" => "Mary Jane");

and a variable
Code:
my $who_user = `who am i|awk '{ print \$1F }'`;

How do I use exists to check if the variable value is present in the hash

Code:
if (exists($users{"$who_user"}))

is not giving the desired output.



Thanks!
Last edited by neil.k; 05-29-2012 at 04:32 AM..
# 2  
Old 05-29-2012
Code:
my $who_user = `whoami`

# 3  
Old 05-29-2012
@balajesuri not sure what you are trying to imply.

The variable who_user will essentially hold a value which I need to check against the keys in the hash user. Whether it's whoami or what I have defined is immaterial to my question.

And, I defined whoami as such, because I wanted to get the login user. Vanilla whoami will not give that, once you su as root or any other user.

Thanks!
# 4  
Old 05-29-2012
Code:
%users = ("abc1" => "John Doe",
                 "xyz2" => "Mary Jane");
open (WH,'whoami |');
my $who_user= <WH>;
chomp($who_user);
print $users{$who_user},"\n" if (exists($users{"$who_user"}));

# 5  
Old 05-29-2012
Pure Perl:
Code:
my $user = getlogin;

or
Code:
my $user = $ENV{"USER"};

# 6  
Old 05-29-2012
@balajesuri I am not sure if you understood my question. Thanks anyways.

The reason my if was not working is because, I had an extra space maybe in the output of my unix command. I used chomp , and it worked like a charm.
# 7  
Old 05-29-2012
@niel.k: I understood your question. My question is, why not use a pure perl functionality to get the username like "getlogin" or "$ENV{"user"}" instead of invoking a shell command like "who am i" ???

That way you won't have to invoke a shell, get the value and then chomp it. I hope I'm able to convey what I intend to.
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