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How capture the outputs of Expect.pm?

How capture the outputs of Expect.pm?

How capture the outputs of Expect.pm?

I wrote a piece of perl code to generating ssh keys using Expect.pm. The code can create keys as expected. But I don't know how to capture the finger prints from the output.


use Expect;

my $passwd = "abcdefg";
my $keyFile = './mykey';
my $cmd = qq/ssh-keygen -t rsa -b 2048 -C "my comments" -f $keyFile/;
print "\nCMD: $cmd\n\n";
my @output;
my $session=Expect->spawn($cmd) or die "Error calling external program:  $!\n";
unless ($session->expect(5,"Enter passphrase \(empty for no passphrase\): ")) {};
print $session "$passwd\r";
unless (@output = $session->expect(5,"Enter same passphrase again: ")) {}; # Capture the output
print $session "$passwd\r";
my $i = 1;
foreach my $e (@output) {
  if($e) {
    print "\$i = $i, Type of \$e: #". ref($e) . "#, Value of \$e: #$e#\n";
  else {
    print "$i, NULL Element!\n";

Here is the output:



CMD: ssh-keygen -t rsa -b 2048 -C "my comments" -f ./mykey
Generating public/private rsa key pair.
Enter passphrase (empty for no passphrase):
Enter same passphrase again:
Your identification has been saved in ./mykey.
Your public key has been saved in ./mykey.pub.
The key fingerprint is:
df:aa:35:19:28:06:0e:97:ec:6d:83:26:b9:01:4f:50 my comments
The key's randomart image is:
+--[ RSA 2048]----+
|..E              |
| . . .           |
|. o =            |
| + * +   .       |
|  = = * S .      |
|   = o o . +     |
|  .       = .    |
|         . o     |
|        ...      |
$i = 1, Type of $e: ##, Value of $e: #1#
2, NULL Element!
$i = 3, Type of $e: ##, Value of $e: #Enter same passphrase again: #
$i = 4, Type of $e: ##, Value of $e: #
5, NULL Element!
$i = 6, Type of $e: #Expect#, Value of $e: #Expect=GLOB(0x1e74b38)# 

I guess the info is in the Glob? But how to parse the Glob?

Thanks for the help.

RE: How capture the outputs of Expect.pm?

I got the solution. Hope it helps.

CODE --> perl

my $output;
  my $session=Expect->spawn($cmd) or die "Error calling external program:  $!\n";
    [ qr/passphrase/i, sub { my $self = shift;
        exp_continue; }],
    [ qr/$comments/i, sub { my $self = shift;
        $output = $self->exp_before;
        exp_continue; }],
  print $output; 

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