use CGI qw/:standard/; print header; #### BEGIN { require CGI; CGI->import( ':standard' ); } print header; #### require CGI; CGI->import( ':standard' ); print header; #### Unquoted string "header" may clash with future reserved word at test.pl line 12. Name "main::header" used only once: possible typo at test.pl line 12. print() on unopened filehandle header at test.pl line 12.