I have a subrouting that outputs a list of FQDN's, separated by new lines:
x1.server.com
s2.sys.com
5a.fdsf.com
^^ It's in this format, so there's no pattern other than {variable text}.{variable text}.{variable text}
My question is how would I be able to get THIS output as the input of a foreach statement so that I can iterate through each FQDN?
NB: You say the sub outputs a list, but I assume what you mean is that it outputs a string. Otherwise, this question is moot.
Just split the output on newline. Assuming the subroutine is called subname:
for my $fqdn (split /\n/, subname())
As Brian Roach notes in the comments, the optimal solution is to make the subroutine return a list instead of a string. However, that may not be a viable solution for you. Either way, if you wish to try it, simply add the split at the appropriate place in the subroutine instead. E.g.:
sub foo {
...
#return $string;
return split /\n/, string;
}
If you want to get advanced, you may make use of the wantarray function, which detects in which context the subroutine is called:
sub foo {
...
return $string unless wantarray;
return split /\n/, string;
}
While this is very cute, it can lead to unwanted behaviour unless you know what you are doing.
push @results,$domain and then return @results into their respected parts of the subroutine and then called the foreach loop like foreach $host (get_mirror_list()) { and it worked beautifully. I'm not an expert at perl so any expert advice I can get I try to implement that was rather than the easy way, although, it did seem easier to do it this way. Thanks!
split /^/m, $_, -1 instead of split /\n/, $_.my $data = mySubRoutine()
# Data now contains one FQDN per line
foreach (my $line = split(/\n/,$data))
{
doStuffWith($line);
}
I wonder if you really mean that your subroutine "outputs" a list - i.e. that it prints the list to STDOUT. Do you have something like this?
#!/usr/bin/perl
use strict;
use warnings;
use 5.010;
sub print_list_of_fqdns {
say "x1.server.com\ns2.sys.com\n5a.fdsf.com";
}
print_list_of_fqdns();
If that's the case then you need to be a bit clever and re-open STDOUT onto a variable.
#!/usr/bin/perl
use strict;
use warnings;
use 5.010;
sub print_list_of_fqdns {
say "x1.server.com\ns2.sys.com\n5a.fdsf.com";
}
sub get_list_of_fqdns {
# Declare a buffer
my $string;
# Open a filehandle that writes to the buffer
open my $fh, '>', \$string or die $!;
# Set your new filehandle to the default output filehandle
# (taking a copy of the original one)
my $old_fh = select $fh;
# Call the function. This will now write the list to the
# variable $string instead of STDOUT
print_list_of_fqdns();
# Split $string to get the individual FQDNs
my @fqdns = split /\n/, $string;
# Replace the old default output filehandle
select $old_fh;
# Return the list of FQDNs
return @fqdns;
}
say join ' / ', get_list_of_fqdns();
