Save terminal output to variable in expect/tcl

Question

Hej all, I have to use an interactive program and I want to automatize it with expect. My experiences in Linux and scripting is not the best. So this is the program output:

enter minimum cross-correlation threshold: 0.15
enter the range and azimuth error thresholds: 1.6 1.0

range, azimuth error thresholds: 1.60000     1.00000
cross-correlation threshold: 0.15000
*
*
*
model fit std. dev. (samples) range: 0.5298   azimuth: 0.4166
set new error bounds? (0: no, 1: yes): 0

The first two lines and the last one are interactive. So with expect and send it was not a problem to enter the thresholds for one time. But I want to iterate this process. Therefore I have to save the results "range: 0.5298 azimuth: 0.4166" into two variables and then run again until I get good results e.g. "range: 0.02 azimuth: 0.02".

Anyone have an idea how I can store the results, compare them, and iterate the process?

That works:

#!/usr/bin/expect
spawn ./offset_fitm_exp
expect "enter minimum cross-correlation threshold:" { send "0.15\r" }
expect "enter the range and azimuth error thresholds:" { send "1.6 1.0\r" }
expect "set new error bounds? (0: no, 1: yes):" { send "0\r" }
interact

Thanks for your help! Bjoern

Solution

To automate the iteration, you can do this:

#!/usr/bin/expect

spawn ./offset_fitm_exp

set range   1.6
set azimuth 1.0

while {true} {
    expect "enter minimum cross-correlation threshold:"
    send "0.15\r" 

    expect "enter the range and azimuth error thresholds:" 
    send "$range $azimuth\r"

    expect -re {range: ([0-9.]+)   azimuth: ([0-9.]+} {
        set range   $expect_out(1,string)
        set azimuth $expect_out(2,string)
    }

    expect "set new error bounds? (0: no, 1: yes):" { 
        if {$range > 0.02 || $azimuth > 0.02} {
            send "1\r"
        } else {
            send "0\r" 
            break
        }
    }
}

interact

Comments

[kos]

Can you add what you have already? The answer will probably need to be integrated deeply with it.

[j0h]

is the zero after the "):" a default output, or did you put that in?

[Piotr De]

I added the code now. I put it in

[j0h]

wait... are you hitting enter at each one of those lines? I thought that was program output. one potential problem i see is that ":" is used in places besides the prompt.

[Piotr De]

No, not at each line. I only hit enter after I put the values in (lines 1,2 and 10)

[j0h]

Do you have source code for the program? (thinking that might be significantly easier to make the automation happen)

[Piotr De]

unfortunately not

[fiatux]

This question is more relevant for Stack Overflow, not askubuntu