How to properly set and get echo status of the terminal associated with a spawned process in expect(1)?
stty -echo executed immediately prior to spawn does not seem to affect the spawned terminal. While set stty_init -echo does, I found no equivalent for querying echo status.
The only hack I found to work on my machine was to use stty(1) as follows and then parse its output:
spawn sh -c "$main_command && stty -a"
However, I'm sceptical of robustness of that hack.
There's also tty_spawn_id, which I thought I could use as an argument to the stty expect command, but its contents make no sense to me: it's e.g. exp5 and not /dev/ttys5, which I would expect.
After spawn, the pty name is saved to $spawn_out(slave,name). You can then use stty(1):
$ expect -c 'spawn sleep 1; set pty $spawn_out(slave,name); puts $pty; puts [exec stty -a --file $pty]; expect eof'
spawn sleep 1
/dev/pts/10
speed 38400 baud; rows 57; columns 168; line = 0;
intr = ^C; quit = ^\; erase = ^?; kill = ^U; eof = ^D; eol = <undef>;
eol2 = <undef>; swtch = <undef>; start = ^Q; stop = ^S; susp = ^Z; rprnt = ^R;
werase = ^W; lnext = ^V; discard = ^O; min = 1; time = 0;
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