# you can name your arrays a,b,c,d,e if you want to,
# but I won't
my (@jobNumbers, @customerNames, @telephoneNumbers,
    @agencyReferences, @statusDescriptions);

# assuming you're reading from STDIN, or
# files named on the command line...
while(<>) {
   if(!/
        (.{6}) # job number, $1
        (.{10}) # customer name, $2
        (.{10}) # telephone number, $3
        (.{10}) # agency reference, $4
        (.{64}) # status description, $5, adjust to skip spaces
      /x) # allow comments and whitespace in regex
   { 
       warn "Skipping badly formatted record '$_'";
       next;
   }
   push @jobNumbers, $1;
   push @customerNames, $2;
   push @telephoneNumber, $3;
   push @agencyReferences, $4;
   push @statusDescriptions, $5;
}

##</code><code>##

# same arrays as above
while(<>) {
    if(length<101) { # 1 more for newline
         chomp;
         warn "Record '$_' too short, skipping";
         next;
    }
    push @jobNumbers, substr $_,0,6;
    push @customerNames, substr $_,6,10;
    push @telephoneNumbers, substr $_,16,10;
    push @agencyReferences, substr $_,26,10;
    # adjust either start or end if you need to skip spaces
    push @statusDescriptions, substr $_,36,64;
}