cvs commit: perlfaq perlfaq.pod perlfaq5.pod

cvsuser     02/09/04 17:48:40

  Modified:    .        perlfaq.pod perlfaq5.pod
  Log:
  * How can I use Perl's C<-i> option from within a program?
      + new answer from mjd
  
  Revision  Changes    Path
  1.12      +5 -1      perlfaq/perlfaq.pod
  
  Index: perlfaq.pod
  ===================================================================
  RCS file: /cvs/public/perlfaq/perlfaq.pod,v
  retrieving revision 1.11
  retrieving revision 1.12
  diff -u -w -r1.11 -r1.12
  --- perlfaq.pod	4 Sep 2002 22:30:10 -0000	1.11
  +++ perlfaq.pod	5 Sep 2002 00:48:40 -0000	1.12
  @@ -1,6 +1,6 @@
   =head1 NAME
   
  -perlfaq - frequently asked questions about Perl ($Date: 2002/09/04 22:30:10 $)
  +perlfaq - frequently asked questions about Perl ($Date: 2002/09/05 00:48:40 $)
   
   =head1 DESCRIPTION
   
  @@ -623,6 +623,10 @@
   =item *
   
   How do I count the number of lines in a file?
  +
  +=item *
  +
  +How can I use Perl's C<-i> option from within a program?
   
   =item *
   
  
  
  
  1.25      +26 -1     perlfaq/perlfaq5.pod
  
  Index: perlfaq5.pod
  ===================================================================
  RCS file: /cvs/public/perlfaq/perlfaq5.pod,v
  retrieving revision 1.24
  retrieving revision 1.25
  diff -u -w -r1.24 -r1.25
  --- perlfaq5.pod	4 Sep 2002 22:39:29 -0000	1.24
  +++ perlfaq5.pod	5 Sep 2002 00:48:40 -0000	1.25
  @@ -1,6 +1,6 @@
   =head1 NAME
   
  -perlfaq5 - Files and Formats ($Revision: 1.24 $, $Date: 2002/09/04 22:39:29 $)
  +perlfaq5 - Files and Formats ($Revision: 1.25 $, $Date: 2002/09/05 00:48:40 $)
   
   =head1 DESCRIPTION
   
  @@ -80,6 +80,31 @@
       close FILE;
   
   This assumes no funny games with newline translations.
  +
  +=head2 How can I use Perl's C<-i> option from within a program?
  +
  +C<-i> sets the value of Perl's C<$^I> variable, which in turn affects
  +the behavior of C<< <> >>; see L<perlrun> for more details.  By
  +modifying the appropriate variables directly, you can get the same
  +behavior within a larger program.  For example:
  +
  +     # ...
  +     {
  +        local($^I, @ARGV) = ('.orig', glob("*.c"));
  +        while (<>) {
  +           if ($. == 1) {
  +               print "This line should appear at the top of each file\n";
  +           }
  +           s/\b(p)earl\b/${1}erl/i;        # Correct typos, preserving case
  +           print;
  +           close ARGV if eof;              # Reset $.
  +        }
  +     }
  +     # $^I and @ARGV return to their old values here
  +
  +This block modifies all the C<.c> files in the current directory,
  +leaving a backup of the original data from each file in a new
  +C<.c.orig> file.
   
   =head2 How do I make a temporary file name?