PYK 2016-02-13:
Expect is typically used to automate interaction with a program, but it can also be used to mediate an interaction. Here is a small example where both user input and program output is monitored:
#! /usr/bin/env expect
set timeout -1
proc main {argv0 argv} {
if {[llength $argv]} {
spawn {*}$argv
}
expect_background {
Ni! {
send_user "[lindex $argv 0] just said, \"Ni!\""
}
}
expect_user {
Ni! {
send_user {You must not say, "Ni!"}
exp_continue
}
-re . {
send $expect_out(buffer)
exp_continue
}
}
}
main $argv0 $argvAn alternate way to structure this is:
#! /bin/env expect
set timeout -1
proc main {argv0 argv} {
if {[llength $argv]} {
spawn {*}$argv
}
expect_after {
-i $::user_spawn_id Ni! {
send_user {You may not say, "Ni!"}
exp_continue
}
-re . {
send $expect_out(buffer)
exp_continue
}
}
expect {
Ni! {
send_user "[lindex $argv 0] just said, \"Ni!\""
exp_continue
}
-re . {
exp_continue
}
}
}
main $argv0 $argv
