my @flist = qw'

1st-device-CA_Eth.0/1

2nd-device-TX_Gig.1/1

'; 


print "@flist\n"; 


for my $file (@flist) { 


    $file =~ s{\_[^_]+$}{, }; 

    print "$file\n"; 

} 
 
##</code><code>##

1st-device-CA_Eth.0/1 

2nd-device-TX_Gig.1/1
 


1st-device-CA, 

2nd-device-TX,