如何检查期望块中命令的成功或失败

Question

I have a bash code which uses expect in between to read from terminal through spawn. The code is somewhat as shown:

expect <{cat <<'EOD'
spawn command_whose_success_or_failure_i_want_to_know
interact
EOD
)

The problem is to find the success or failure of "command_whose_success_or_failure_i_want_to_know" within expect block.

Right now when I am doing :

if [ $? -eq 0 ]; then
blah

It is actually checking for expect success and not the inside command which I want to check for. How can I do that here? Thanks

Answer 1

You'll do this (untested):

expect <<'END_EXPECT'
    # if your command takes > 10 seconds to complete, uncomment the next line:
    # set timeout $some_number_of_seconds_or_negative_one

    spawn command_whose_success_or_failure_i_want_to_know
    expect eof

    set result [wait]
    if {[lindex $result 2] == 0} {
        exit [lindex $result 3] ;# exit expect with the command's exit status
    } else {
        error "an operating system error occurred, errno=[lindex $result 3]"
    }
END_EXPECT
exit_status=$?

echo "the command exited with: $exit_status"