Hi there, it looks like you want to do this:
#!/usr/bin/perl
use strict;
use warnings;
my $file = '1140475.txt';;
open my $raw, '<', $file or die "open: $!";
open my $out, '>', "out_$file" or die "close: $!";
while ( my $line = <$raw> ) {
chomp( $line );
my @splits = split ( ',', $line );
print $out "First line, first field: $splits[0]\n";
last;
}
close $out or die "close: $!";
__END__
Output:
$ cat out_1140475.txt
First line, first field: 1424621700
But you should use a module if you can. A lot of people like Path::Tiny because it does the file opening, reading, and chomping, for you. In the example below I use split() on the first element of the array of lines returned by Path::Tiny::path() (there's actually only one line since I set the 'count' attribute), and then I assign the first element of the result of split() to $first.
#!/usr/bin/perl
use strict;
use warnings;
use Path::Tiny qw/ path /;
my $file = '1140475.txt';
my $first = ( split ',', (path($file)->lines( {chomp => 1, count => 1}
+ ))[0] )[0];
print "$first\n";
__END__
Output:
$ perl 1140475-2.pl
1424621700
$
Hope this helps!
The way forward always starts with a minimal test.