my $set_password = '/usr/bin/ssh ' . $master_host . " 'echo \Q$new_pas
+sword\E | /usr/bin/passwd --stdin \Q$username\E'";

[download]

Unfortunately, that won't work if the password contains, for example, a single quote. 

my $master_host  = 'localhost';
my $username     = 'foo';
my $new_password = 'a\'b$c"d|e';

print "pwd: ",$new_password;

my $set_password = '/usr/bin/ssh ' . $master_host . " 'echo \Q$new_pas
+sword\E | /usr/bin/passwd --stdin \Q$username\E'";

print "cmd: ",$set_password;
system $set_password;

__END__
pwd: a'b$c"d|e
cmd: /usr/bin/ssh localhost 'echo a\'b\$c\"d\|e | /usr/bin/passwd --st
+din foo'
sh: Syntax error: Unterminated quoted string

[download]

In other words, a simple quotemeta (\Q) is not the appropriate tool to quote arbitrary strings for the shell. You'd have to use more sophisticated techniques.

In reply to Re^2: passwords with special characters are trying to kill me... no seriously! by Anonyrnous Monk
in thread passwords with special characters are trying to kill me... no seriously! by calmthestorm

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