Shell Programming and Scripting

Sorry for overquoting, but I skip all the answers already made :-) And moderators should also have some fun with my posts.

If you look ag ssh source code, you will notice, that ssh asks for password in a specific manner:
https://github.com/openssh/openssh-p...ter/readpass.c

Code:

/*
 * Reads a passphrase from /dev/tty with echo turned off/on.  Returns the
 * passphrase (allocated with xmalloc).  Exits if EOF is encountered. If
 * RP_ALLOW_STDIN is set, the passphrase will be read from stdin if no
 * tty is available
 */

ssh doesn't write to standard output, where expect waits for the string "password", that's why you can't handle sftp password prompt with your script.

I didn't want to waste too much time with your script and still don't know the correct answer, but:

- your script works for me on my RHEL6 with expect 5.44

Code:

$ cat test.expect 
#!/usr/bin/expect -f
spawn sftp test@localhost
expect "password:"
send "database123#\n"
$ expect -v
expect version 5.44.1.15
$ ssh -V
OpenSSH_5.3p1, OpenSSL 1.0.1e-fips 11 Feb 2013
$ ./test.expect 
spawn sftp test@localhost
Connecting to localhost...
test@localhost's password: 
Permission denied, please try again.

(Permission denied is because I don't have user test on the box)

- your script doesn't work on my Macbook.

Code:

$ expect -v
expect version 5.45
$ ssh -V
OpenSSH_6.2p2, OSSLShim 0.9.8r 8 Dec 2011

- your script with small corrections works on my Macbook.

Code:

$ cat test.expect 
#!/usr/bin/expect -f
spawn sftp test@localhost
expect_tty "password:"
send "database123#\r\n"
$ expect -v
expect version 5.45
$ ssh -V
OpenSSH_6.2p2, OSSLShim 0.9.8r 8 Dec 2011
$ ./test.expect 
spawn sftp test@localhost
Password:
Password:^C

It asks the second time for the password, because I don't have user test ;-)
I hope you noticed 2 small corrections I've made:

- first I used expect_tty instead of expect, because OpenSSH uses /dev/tty as output device and not stdout
- second I added \r before \n to password line, because we use /dev/tty which requires (afair) both symbols and not POSIX-standard stdout.

As some moderators write, I hope it helps ... to find a solution to your expect problem.