Question

I want to write a bash script that will execute one command in the script, and the command need read some thing as password. So how can I pass the password to the command in the script?

$ota_gen -k $ota_key -i $1 -p $ota_tools $2 $ota_out_file

ota_key is a private key that need to be visited with a password, so how can I do it?
thank you.

ps: thanks hlovdal for help.
expect maybe what can help. But I don’t know if it can interact with bash script, such as how to pass parameters from script to expect.

Answer 1

A quite common tool for feeding programs with proper input (like for instance passwords) non-interactively is the tool expect. The following example is given on the wikipedia page:

# Assume $remote_server, $my_user_id, $my_password, and $my_command were read in earlier 
# in the script.
# Open a telnet session to a remote server, and wait for a username prompt.
spawn telnet $remote_server
expect "username:"
# Send the username, and then wait for a password prompt.
send "$my_user_id\r"
expect "password:"
# Send the password, and then wait for a shell prompt.
send "$my_password\r"
expect "%"
# Send the prebuilt command, and then wait for another shell prompt.
send "$my_command\r"
expect "%"
# Capture the results of the command into a variable. This can be displayed, or written to disk.
set results $expect_out(buffer)
# Exit the telnet session, and wait for a special end-of-file character.
send "exit\r"
expect eof