#!/usr/bin/env bash

# @(#) s1	Demonstrate perl method of keeping field separators intact.

# Utility functions: print-as-echo, print-line-with-visual-space, debug.
# export PATH="/usr/local/bin:/usr/bin:/bin"
LC_ALL=C ; LANG=C ; export LC_ALL LANG
pe() { for _i;do printf "%s" "$_i";done; printf "\n"; }
pl() { pe;pe "-----" ;pe "$*"; }
db() { ( printf " db, ";for _i;do printf "%s" "$_i";done;printf "\n" ) >&2 ; }
db() { : ; }
C=$HOME/bin/context && [ -f $C ] && $C perl

FILE=${1-data1}

pl " Input data file $FILE:"
pe " ( Separators: any run of dash, TAB SPACE, comma, equal-sign)"
od -bc $FILE

pl " Results, change data field 6 to \".\", keeping all separators:"
./p1 data1 |
od -bc

pl " perl code:"
cat p1

exit 0

$ ./s1

Environment: LC_ALL = C, LANG = C
(Versions displayed with local utility "version")
OS, ker|rel, machine: Linux, 2.6.26-2-amd64, x86_64
Distribution        : Debian 5.0.8 (lenny, workstation) 
bash GNU bash 3.2.39
perl 5.10.0

-----
 Input data file data1:
 ( Separators: any run of dash, TAB SPACE, comma, equal-sign)
0000000 141 054 142 055 143 040 040 144 011 145 011 011 146 011 040 040
          a   ,   b   -   c           d  \t   e  \t  \t   f  \t        
0000020 147 075 150 012
          g   =   h  \n
0000024

-----
 Results, change data field 6 to ".", keeping all separators:
0000000 141 054 142 055 143 040 040 144 011 145 011 011 056 011 040 040
          a   ,   b   -   c           d  \t   e  \t  \t   .  \t        
0000020 147 075 150 012
          g   =   h  \n
0000024

-----
 perl code:
#!/usr/bin/env perl

# @(#) p1	Demonstrate method for keeping field separators.
# Field 10 because array index begins at 0, and there is no
# leading separator on the line. So line field 6 is at 11-1 -> 10.

use warnings;
use strict;

my ( $debug, $i, @field );

# Interchange next 2 lines to enable printing of all fields and
# separators in individual components of array "field".
$debug = 1;
$debug = 0;

while (<>) {
  chomp;
  @field = split /([-\s,=]+)/;
  if ($debug) {
    for ( $i = 0; $i < $#field; $i++ ) {
      print STDERR "$i,\"$field[$i]\"\n";
    }
	print STDERR "\n";
  }
  $field[10] = ".";
  print join( "", @field ), "\n";
}