All,

I have file which is of ~1gb, my requirement is to replace the specific lines specified range of characters with the provided string. I am using perl 5.8, below is my code. Due to the interpolation oneliners are not getting the variables vaule.

die "usage: perl $0 file_nm line_nb col_start col_end replacement \n" 
+unless @ARGV;
die "Invalid number of arguments \nusage: perl $0 file_nm line_nb col_
+start col_end replacement \n" if @ARGV ne 5;

my ($file_nm,$line_nb,$col_start,$col_end,$string)=@ARGV;

chomp($content=`perl -ne "print if $. == ${line_nb}" $file_nm`); #get 
+the specific line from file

chomp ($replacement=`perl -ne "substr($content, $col_start, $col_end, 
+$string);print $content"`); #get the replaced line
#print "New content \n$content \n";
`perl -pi -e "s/$content/$replacement/" $file_nm`; #now substitute the
+ whole line with the new replaced line
[download]

Arguments to the script are File name line number ,in which the replacement should take place replacement start position replacement end position string to replace with Suggestions are welcome

--- Update --- Wrote a perl script finally

use File::Basename;
die "usage: perl $0 file_nm line_nb pos_start-pos_end replacement \n" 
+unless @ARGV;
die "Invalid number of arguments \nusage: perl $0 file_nm line_nb pos_
+start pos_end replacement \n" if @ARGV ne 5;

my ($file_nm,$line_nb,$pos,$string)=@ARGV;
my ($pos_start,$pos_end)=split (/-/,$pos);
$file_nm=File::Basename::basename($file_nm);

open(READ_HN,"$file_nm") or die "Cant open $file_nm $! \n";
open(WRITE_HN,">${file_nm}.updated") or die "Cant write to ${file_nm}.
+updated $! \n";


#chomp($content=`perl -ne "print if $. == ${line_nb}" $file_nm`);
while(<READ_HN>)
{
    if ($. == $line_nb)
    {
        substr($_, $pos_start, $pos_end, $string);
    }
    print WRITE_HN "$_\n";
}


close(WRITE_HN);
close(READ_HN);
[download]

---

---

Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!

Titles consisting of a single word are discouraged, and in most cases are disallowed outright.

Read Where should I post X? if you're not absolutely sure you're posting in the right place.

Please read these before you post! —

• How do I compose an effective node title?
• How do I post a question effectively?
• Markup in the Monastery

Posts may use any of the Perl Monks Approved HTML tags:

a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr

You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)

	For:		Use:
	&		&
	<		&lt;
	>		&gt;
	[		&#91;
	]		&#93;

Link using PerlMonks shortcuts! What shortcuts can I use for linking?

See Writeup Formatting Tips and other pages linked from there for more info.