As you know what the first 2 fields are and what the last 4 fields are everything in between would be the name. So you could re-join the fields in the middle, possibly distorting the white space. 

use strict;
use warnings;
<DATA>;
while(<DATA>){
  chomp;
  my @line = split /\s+/;
  my $from = join( " ", splice( @line, 2, $#line-5) );
  my ($reqid, $dest, $date, $time, $pages, $rcv) = @line;
  print join "|", ($reqid, $dest, $from, $date, $time, $pages, $rcv);
  print "\n";
}
__DATA__

REQID     DEST             FROM                     DATE   TIME    nPa
+ges  RCV
138454  mail_room     Marco's Pizza         12/26 21:52    1  rcv     
138446  custsvc      973 618 0577          12/26 18:44    1  rcv     
138445  county2       spam                  12/26 18:41    3  rcv     
138444  custsvc      spam                  12/26 18:30    1  rcv
138439  county2       7182737253            12/26 17:54    2  rcv     
138438  county2       Acme Products, Inc.   12/26 17:52    1  rcv

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In reply to Re: How to split line with varying number of tokens? by hdb
in thread How to split line with varying number of tokens? by zBernie

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