escape special charactor

[sin kanti]

Hi all,

I write script to send password to unix shell.
But i found out that if the password contain special charactor such as &,
Shell will interpret it as background process.
So, it have to use \& instead.

Is there any function can detect special char?
and return it is escape form? ( like \& )

i found similar function in Regexp.escape, but it can't detect &

any idea?

sinchai

 

[Joel VanderWerf]

Hi all,

I write script to send password to unix shell.
But i found out that if the password contain special charactor such as &,
Shell will interpret it as background process.
So, it have to use \& instead.

Is there any function can detect special char?
and return it is escape form? ( like \& )

i found similar function in Regexp.escape, but it can't detect &

Are you using #system? If so, you can prevent the shell from expanding
things by passing each shell argument as a separate ruby argument:

irb(main):001:0> system "echo foo&"
foo
=> true
irb(main):002:0> system "echo", "foo&"
foo&
=> true

 

[sin kanti]

i use
$output = `command`
because i want to puts $output later

sinchai

 

[Robert Klemme]

i use
$output = `command`
because i want to puts $output later

Two options: use single quotes when building the command like:

cmd = "your_program -p '#{password}'"

escape the password:

cmd = "your_program -p #{password.gsub(/&/, '\\\\&')}"

I'd choose optin 1 because it's simpler and safer (note though that you
need similar escaping if the password contains single quotes).

Kind regards

robert