Seeing your regex s/\t||\r||\n||\f//g I think you should check the documentation of perlretut, perlrequick, and perlre.

I assume you wanted to remove any occurence of \t, \r, \n or \f.

You could use a character class in regex for this

$text =~ s/[\t\r\n\f]//g

or you could use tr///d (see tr/SEARCHLIST/REPLACEMENTLIST/cds)

$text =~ tr/\t\r\n\f//d

In reply to Re: Where to add substitution? by linuxer
in thread Where to add substitution? by reclusivemonkey

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