how to expect eof with expect+pty

[Simon Strandgaard]

using gnupg to encrypt a file with only a passphrase.

prompt> echo 'hello world' >> test
prompt> gpg -c test
Enter passphrase:
Repeat passphrase:
prompt>

note: I have not shown the many backspaces.



however if there already exists a 'test.gpg' file
then there is third question.


prompt> echo 'hello world' >> test
prompt> gpg -c test
Enter passphrase:
Repeat passphrase:
File `test.gpg' exists. Overwrite? (y/N)



I want to listen for:
'Enter passphrase: '
'Repeat passphrase: '
eof?


In case I get something else than eof? then
I want to raise an error.


--
Simon Strandgaard


File.open("test", "a+") do |f|
500000.times { f.write("helloworld") }
end

require 'pty'
require 'expect'
PTY.spawn("gpg -c test") do |r,w,pid|
w.sync = true
r.expect("Enter passphrase: ", 1) do |e|
raise unless e
w.puts "secretpassword"
end
r.expect("Repeat passphrase: ", 1) do |e|
raise unless e
w.puts "secretpassword"
end

puts "eof=#{r.eof}"
# how to read eventual data
# how to expect eof?
end

system('ls test*')





# output when running the program
prompt> ruby a.rb
eof=false
test test.gpg
prompt>

 

[Simon Strandgaard]

I want to listen for:
'Enter passphrase: '
'Repeat passphrase: '
eof?

[snip]


Ok I got a partial solution.. now it would be nice if I could access
the string accumlated in readlines when this thing timeouts.

--
Simon Strandgaard

File.open("test", "a+") do |f|
500000.times { f.write("helloworld") }
end

require 'expect'
require 'timeout'
require 'pty'

timeout(3) do
PTY.spawn("gpg -c test") do |r,w,pid|
w.sync = true
r.expect("Enter passphrase: ", 1) do |e|
raise unless e
w.puts "secretpassword"
end
r.expect("Repeat passphrase: ", 1) do |e|
raise unless e
w.puts "secretpassword"
end

r.readlines
puts "eof=#{r.eof}"
end
end

system('ls test*')

 

[Simon Strandgaard]

I want to listen for:
'Enter passphrase: '
'Repeat passphrase: '
eof?

[snip]


Ok I got a partial solution.. now it would be nice if I could access
the string accumlated in readlines when this thing timeouts.

[snip]

Now its working.. thanks ruby-talk


require 'expect'
require 'timeout'
require 'pty'

def gnupg_encrypt(filename, passphrase)
msg = ""
PTY.spawn("gpg -c #{filename}") do |r,w,pid|
w.sync = true
r.expect("Enter passphrase: ", 1) do |e|
raise "Enter passphrase" unless e
w.puts passphrase
end
r.expect("Repeat passphrase: ", 1) do |e|
raise "Repeat passphrase" unless e
w.puts passphrase
end
timeout(1) do
msg += r.getc.chr until r.eof
end
end
if msg =~ /\S/
p msg
return -1
end
puts "OK"
return 0
rescue Timeout::Error => e
p e, msg
return -2
rescue => e
p e
return -3
end


if $0 == __FILE__
File.open("test", "a+") do |f|
500000.times { f.write("helloworld") }
end

gnupg_encrypt("test", "secretpassword")
system('ls test*')
end

 

[Jonathan Hudson]

I want to listen for:
'Enter passphrase: '
'Repeat passphrase: '
eof?

[snip]


Ok I got a partial solution.. now it would be nice if I could access
the string accumlated in readlines when this thing timeouts.

[snip]

Now its working.. thanks ruby-talk

If you don't care about overwriting, doesn't "--yes" remove the
overwrite prompt (it does interactively) ?

PTY.spawn("gpg --yes -c #{filename}")

 

[Simon Strandgaard]

If you don't care about overwriting, doesn't "--yes" remove the
overwrite prompt (it does interactively) ?

PTY.spawn("gpg --yes -c #{filename}")

Its for my daily repository backup. I didn't knew about
the '--yes' option, this helps alot. Thanks