UNIX for Dummies Questions & Answers

# /mytmp is a direcotry on a filesystem with enough free space 184GB
# /dest is a directory on a disk with enough free space.  184G
export TMPDIR=/mytmp
sort -k 1.1,1.20 -o /dest/INITIATE_FINAL_ALL_810804405.dat \
     INITIATE_FINAL_ALL_810804405.dat

awk '{ file=substr($0,1,1); print $0 > file".txt"} INITIATE_FINAL_ALL_810804405.dat

> cat rawfile
Joe_________12_Main_St__A001________LX
Benny_______5_Spring____A002________LX
Will________2_A_St______A003________LX
Carl________15_X_Way____A004________LX
Henry_______85_Alpo_____B007________MX
Cal_________923_V_St____A006________RX
Holly_______62_US_______A005________TX
Will________9_Strong____A007________SX
Kate________101_Smile___C002________SX

> cat rawsorted 
Joe_________12_Main_St__A001________LX
Benny_______5_Spring____A002________LX
Kate________101_Smile___C002________SX
Will________2_A_St______A003________LX
Carl________15_X_Way____A004________LX
Holly_______62_US_______A005________TX
Cal_________923_V_St____A006________RX
Henry_______85_Alpo_____B007________MX
Will________9_Strong____A007________SX

> cat psff
#! /usr/bin/perl
# start of perl
# use strict;

# set vars
 $source = "rawfile";
 $outfile = ">rawsorted";

# open the source file
open(SOURCE,$source);
@rawdata=<SOURCE>;
# open the output file
open(OUTFILE,$outfile);

# sort at position 25 (note the 24) for length of 10
# sort in reverse order, hence the b before a in sort{ cmp } statement
# sort in forward order, hence the a before b in sort{ cmp } statement
@sorted = map{$_->[0]}
               sort {$a->[1] cmp $b->[1]}
               map {[$_,substr($_,24,10)]} @rawdata;

# write the sorted file to disk
print OUTFILE @sorted;

close SOURCE;
close OUTFILE;