Shell Programming and Scripting

#!/bin/ksh
IAm=${0##*/}
Usage='Usage: %s [count=file_count] [filename_format="format"] [pat="ERE"] \\
		[rep_format="format"] file
where the optional operands specify:
	count=file_count
		The number of output files to create from the file operand.
		Default 1000.
	filename_format="format"
		The sprintf() format string used to create output file
		pathnames.  Default value is "nomefile%04d.txt".
	pat="ERE"
		An extended regular expression defining the text to be matched
		in file.  Default value is "4e4k_lig[0-9]{0,4}.pdbqt".
	rep_format="format"
		The sprintf() format string used to create the replacement text
		for each string matching pat in file.  Default value is
		"4e4k_lig%04d.pdbqt".
Note that the file operand must be presented after any optional operands.
'
if [ $# -lt 1 ]
then	printf "$Usage" "$IAm" >&2
	exit 1
fi
awk '
BEGIN {	count = 1000
	filename_format = "nomefile%04d.txt"
	pat = "4e4k_lig[0-9]{0,4}.pdbqt"
	rep_format = "4e4k_lig%04d.pdbqt"
}
{	l[NR] = $0
}
END {	for(i = 1; i <= count; i++) {
		fn = sprintf(filename_format, i)
		rep = sprintf(rep_format, i)
		for(j = 1; j <= NR; j++) {
			line = l[j]
			gsub(pat, rep, line)
			print line > fn
		}
		close(fn)
	}
}' "$@"

./script_name pat="mionome0001.pdb" rep_format="mionome%04d.pdb" file1

#!/usr/bin/perl
use strict;
use warnings;

my @template_lines;
my ($target, $match);
my $search = "4e4k_lig"; # Change me to the pattern you want to match.

while (<>) {
    push @template_lines, $_;
    /$search/ and $target = ($. -1) and $match = $_;
}
die unless $target;

my $amount_of_files = 10; # Change me to 1000.
my $file_base = "nomefile"; # Change me to a file base name.

for my $x (1 .. $amount_of_files){
    my $serial = sprintf "%04d", $x;
    my $mod = $match;
    $mod =~ s/$search/$search$serial/;
    $template_lines[$target] = $mod;
    createfile($serial);
}

sub createfile {
    my $n = shift;
    open my $fh, '>', "$file_base$n.txt" or die "Could not write file: $!";
    print $fh @template_lines;
    close $fh;
}