Where to start. First, what you are trying to do is invalid. Unless you have fixed length records, it is not possible to insert a record into the middle of a text file. That is the case regardless of the language. The best you can do is to read a file then write out to a different one, inserting the new record in the correct place in the new file.

Opening a file for append and read will position the current file position to end-of-file, so you will not read anything.

The open statement requires parentheses around the argument list when you use the high precendent || operator. Or use the low precedence or.

print on its own writes to STDOUT, not to a file.

By convention, it is not a good idea to use UPPERCASE for your own variable names, like $NAMES.

This may get you what you want:
#!/usr/bin/perl 
use strict;
use warnings;  


my $infile = '/home/yanni/scripts/testfiles/list_names';
my $outfile = "$infile.tmp";

open (my $in,  '<', $infile ) || die "Can't open $infile $!\n";
open (my $out, '>', $outfile) || die "Can't open $outfile $!\n";

while (<$in>)
{   
    print $out $_;
    if ($.== 3) {print $out "Simon\n";} 
}

close ($in);
close ($out);
rename ($outfile, $infile) || die "Unable to rename: $!";

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Update: On second thought, the record length has nothing to do with it if you want to insert (I was thinking of an overwrite). You would still have to read the records in first somehow.

In reply to Re: Inserting a line in the middle of a text by cdarke
in thread Inserting a line in the middle of a text by goude

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