... FAQ89CHAPTER 4 Perl as a (better) sed command 4. 1 A brief history of sed 89 4. 2 Shortcomings of sed 91 4. 3 Performing substitutions 93 4. 4 Printing lines by number 100 4. 5 Modifying templates 101 4. 6 ... case differencesMatches perl , PERL , Perl , and so on in $data.$data =~ / perl /xi Same, except x requests extended syntaxMatches perl , PERL , Perl , and so on in $data. Because ... letters, digits, and dots. Domains ending in two-letter country codes other than.us are “foreign” (to Americans, at least); for instance, the .pl domain stands for Poland, and .au stands for Australia.22Although...