Opening a text file as a hash and searching within that hash - perl

Question

I have an assignment to write a Perl file to open a text file of IP addresses and their hostnames, separated by a new line, and load it into a hash. I'm then supposed to ask for user input as to what the user would like to search for within the file. If a result is found, the program should print the value and key, and ask for input again until the user doesn't input anything. I'm not even close to the end, but need a bit of guidance. I've cobbed together some code from here and through using some Google-Fu.
Here's my work in progress:
#!/usr/bin/perl
print "Welcome to the text searcher! Please enter a filename: ";
$filename = <>;
my %texthash = ();
open DNSTEXT, "$filename"
or die! "Insert a valid name! ";
while (<DNSTEXT>) {
chomp;
my ($key, $value) = split("\n");
$texthash{$key} .= exists $texthash{$key}
? ",$value"
: $value;
}
print $texthash{$weather.com}
#print "What would you like to search for within this file? "
#$query = <>
#if(exists $text{$query}) {
As is probably glaringly obvious, I'm quite lost. I'm not sure if I'm inserting the file into the hash correctly, or how to even print a value to debug.

Answer 1

The problem here is we don't know what the input file looks like. Assuming that the input file somehow looks like:
key1,value1
key2,value2
key3,value3
(or other similar manner, in this case the key and value pair are separated by a comma), you could do this:
my %text_hash;
# the my $line in the while() means that for every line it reads,
# store it in $line
while( my $line = <DNSTEXT>) {
chomp $line;
# depending on what separates the key and value, you could replace the q{,}
# with q{<whatever is between the key and value>}
my ( $key, $value ) = split q{,},$line;
$text_hash{$key} = $value;
}
But yeah, please tell us what the content of the file looks like.