Issue
I can ask the user to press Enter by using read
, and have him wait by calling sleep
. But I can’t think of a way of doing both at the same time. I would like the user to be given the choice:
Press Ctrl+C to Cancel, Enter to continue or just wait 10 seconds
How can I do that?
Solution
In bash
(1), read
has a -t
option where you can specify a timeout. From the manpage:
read [-ers] [-u fd] [-t timeout] [-a aname] [-p prompt] [-n nchars] [-d delim] [name ...]
-t timeout:
cause read to time out and return failure if a complete line of input is not read within timeout seconds. This option has no effect if read is not reading input from the terminal or a pipe.
Transcript below (without hitting ENTER):
$ date ; read -t 10 -p "Hit ENTER or wait ten seconds" ; echo ; date
Tue Feb 28 22:29:15 WAST 2012
Hit ENTER or wait ten seconds
Tue Feb 28 22:29:25 WAST 2012
Another, hitting ENTER after a couple of seconds:
$ date ; read -t 10 -p "Hit ENTER or wait ten seconds" ; date
Tue Feb 28 22:30:17 WAST 2012
Hit ENTER or wait ten seconds
Tue Feb 28 22:30:19 WAST 2012
And another, hitting CTRL-C:
$ date ; read -t 10 -p "Hit ENTER or wait ten seconds" ; echo ; date
Tue Feb 28 22:30:29 WAST 2012
Hit ENTER or wait ten seconds
(1) If you're doing this in a script, make sure that it's a bash
one. You can do that by adding a shebang line at the start such as one of the following:
#!/usr/bin/env bash
#!/bin/bash
Answered By - paxdiablo Answer Checked By - Pedro (WPSolving Volunteer)