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Full Discussion: In bash, read to a variable with a default value to edit
Top Forums Shell Programming and Scripting In bash, read to a variable with a default value to edit Post 302151291 by drl on Friday 14th of December 2007 09:27:25 AM
Old 12-14-2007
Hi.

Here is a cheap way of doing this:
Code:
#!/usr/bin/env sh

# @(#) s1       Demonstrate setting default value for read variable.

set -o nounset
echo

debug=":"
debug="echo"

## Use local command version for the commands in this demonstration.

echo "(Versions displayed with local utility \"version\")"
version >/dev/null 2>&1 && version bash

echo

default=9900


read -p "Port number (default is $default): " -e t1
if [ -n "$t1" ]
then
  port_number="$t1"
else
  port_number="$default"
fi

echo
echo " Port number is \"$port_number\""

exit 0

Producing (partial copy of interactive session):
Code:
% ./s1

(Versions displayed with local utility "version")
GNU bash 2.05b.0

Port number (default is 9900):

 Port number is "9900"
leap user-problem/220 % ./s1

(Versions displayed with local utility "version")
GNU bash 2.05b.0

Port number (default is 9900): 2001

 Port number is "2001"

This doesn't allow "editing" possibly in the sense you are thinking of, but 1) it puts the default value in the prompt, 2) one can enter a bare RETURN to accept the default value, or 3) enter a new value. Beyond this, as Perderabo noted and as you will see from porter's readline reference, things get complicated ... cheers, drl
 

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LEARN ABOUT DEBIAN

rt-email-group-admin-4

rt-email-group-admin(8) 				     Request Tracker Reference					   rt-email-group-admin(8)

NAME

       rt-email-group-admin - Command line tool for administrating NotifyGroup actions

SYNOPSIS

	   rt-email-group-admin --list
	   rt-email-group-admin --create 'Notify foo team' --group Foo
	   rt-email-group-admin --create 'Notify foo team as comment' --comment --group Foo
	   rt-email-group-admin --create 'Notify group Foo and Bar' --group Foo --group Bar
	   rt-email-group-admin --create 'Notify user foo@bar.com' --user foo@bar.com
	   rt-email-group-admin --create 'Notify VIPs' --user vip1@bar.com
	   rt-email-group-admin --add 'Notify VIPs' --user vip2@bar.com --group vip1 --user vip3@foo.com
	   rt-email-group-admin --rename 'Notify VIPs' --newname 'Inform VIPs'
	   rt-email-group-admin --switch 'Notify VIPs'
	   rt-email-group-admin --delete 'Notify user foo@bar.com'

DESCRIPTION

       This script list, create, modify or delete scrip actions in the RT DB. Once you've created an action you can use it in a scrip.

       For example you can create the following action using this script:

	   rt-email-group-admin --create 'Notify developers' --group 'Development Team'

       Then you can add the followoing scrip to your Bugs queue:

	   Condition: On Create
	   Action:    Notify developers
	   Template:  Transaction
	   Stage:     TransactionCreate

       Your development team will be notified on every new ticket in the queue.

USAGE

       rt-email-group-admin --COMMAND ARGS

COMMANDS

   list
       Lists actions and its descriptions.

   create NAME [--comment] [--group GNAME] [--user UNAME]
       Creates new action with NAME and adds users and/or groups to its recipient list. Would be notify as comment if --comment specified.

   add NAME [--group GNAME] [--user UNAME]
       Adds groups and/or users to recipients of the action NAME.

   delete NAME
       Deletes action NAME if scrips doesn't use it.

   switch NAME
       Switch action NAME from notify as correspondence to comment and back.

   rename NAME --newname NEWNAME
       Renames action NAME to NEWNAME.

   NOTES
       If command has option --group or --user then you can use it more then once, if other is not specified.

AUTHOR

       Ruslan U. Zakirov <ruz@bestpractical.com>

SEE ALSO

       RT::Action::NotifyGroup, RT::Action::NotifyGroupAsComment

perl v5.14.2							    2013-05-22						   rt-email-group-admin(8)
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