PerlIO in Windows PowerShell and CMD.exe
- by Evan Carroll
Apparently, a Perl script I have results in two different output files depending on if I run it under Windows PowerShell, or cmd.exe. The script can be found at the bottom of this question. The file handle is opened with IO::File, I believe that PerlIO is doing some screwy stuff. It seems as if under cmd.exe the encoding chosen is much more compact encoding (4.09 KB), as compared to PowerShell which generates a file nearly twice the size (8.19 KB). This script takes a shell script and generates a Windows batch file. It seems like the one generated under cmd.exe is just regular ASCII (1 byte character), while the other one appears to be UTF-16 (first two bytes FF FE)
Can someone verify and explain why PerlIO works differently under Windows Powershell than cmd.exe? Also, how do I explicitly get an ASCII-magic PerlIO filehandle using IO::File?
Currently, only the file generated with cmd.exe is executable. The UTF-16 .bat (I think that's the encoding) is not executable by either PowerShell or cmd.exe.
BTW, we're using Perl 5.12.1 for MSWin32
#!/usr/bin/env perl
use strict;
use warnings;
use File::Spec;
use IO::File;
use IO::Dir;
use feature ':5.10';
my $bash_ftp_script = File::Spec->catfile( 'bin', 'dm-ftp-push' );
my $fh = IO::File->new( $bash_ftp_script, 'r' ) or die $!;
my @lines = grep $_ !~ /^#.*/, <$fh>;
my $file = join '', @lines;
$file =~ s/ \\\n/ /gm;
$file =~ tr/'\t/"/d;
$file =~ s/ +/ /g;
$file =~ s/\b"|"\b/"/g;
my @singleLnFile = grep /ncftp|echo/, split $/, $file;
s/\$PWD\///g for @singleLnFile;
my $dh = IO::Dir->new( '.' );
my @files = grep /\.pl$/, $dh->read;
say 'echo off';
say "perl $_" for @files;
say for @singleLnFile;
1;
