Ciao,

Prova questo:

Lo lanci cosí: perl file.txt
codice:
#!/usr/bin/perl
  opendir DIR, ".";
  @perlfiles = grep /\.pl/, readdir DIR;
  closedir DIR;

  foreach $file (@perlfiles) {
    open FH, "+<$file";
    
    @file = <FH>;

    seek(FH, 0, 0);
    truncate(FH, 0);

    $line = shift @file;

    print FH "#!c:\\perl\\bin\\perl\n";
    print FH @file;

    close(FH);
    
  }