How do I timeout a "read" command

[Tison]

I want to give the users 10 seconds to press the "ENTER" key.If they do not press "ENTER", perform task A , else if they do press "ENTER", perform task B.
My problem is in getting the "read" command to continue after the 10 seconds have elapsed.

 

[bjverzal]

Can't do it. Since "read" is an internal command to "ksh", there is no sub-process spawned off to check for in the process table (ps -ef), so you can't kill it.

You'll need to write some sort of C program. Perl might be able to do this as well, but I'm not sure.

Bill.

 

[guitarguy]

Try using expect in Perl. It has timeouts and all kinds of neat stuff. I automate alot of telnet/ftp sessions with this tool and reads probably wouldn't be that difficult either.

-------------snip------------------------
#!/usr/bin/perl -w

use Expect;

$command = Expect->spawn("telnet zeus&quot || die "no telnet";

unless($command->expect(10, "login: &quot) {
# timed out
}
print $command &quot;<loginName>\r&quot;;
-------------endsnip---------------------

something like this...

hope it helps.