Look at Tie::File instead. It's included with modern versions of Perl.

With Tie::File you get to use conveniences such as splice, push, shift, and so on.

Another method is to open the input file, open an output file, read the input file line by line, and as you read it, write line by line to the output file, of course skipping output for those lines you wish to drop (next is great for that).

Once you've finished reading the input and writing the output file, unlink the input file, and rename the output file to the same name as the original input file.

That's pretty much what the -i command line switch implements behind the scenes.

$ cat myfile
1st line
2nd line
3rd line
$ perl -ni.bak -e 'next if /^2nd/; print;' myfile
$ cat myfile
1st line
3rd line
$ cat myfile.bak
1st line
2nd line
3rd line
$
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I hope this is of use.

Cheers,

JohnGG

You can also use -p with a goto:


perl -pe 'goto LINE if /^2nd/' myfile
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Which makes since if you look at what it turns into:


$ perl -MO=Deparse -pe 'goto LINE if /^2nd/' myfile
LINE: while (defined($_ = <ARGV>)) {
    goto LINE if /^2nd/;
}
continue {
    print $_;
}
-e syntax OK
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Well, that's something new I've learnt. Thank you. Two things in fact as I've never played with -MO=Deparse before and now I can see how useful it can be.

The only problem with goto is personal in that my first language was Fortran IV; no code blocks and no else clauses meant that your code was full of GO TO's and I became heartily sick of them :)

Cheers,

JohnGG