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Full Discussion: Bash : While Loop behavior
Top Forums UNIX for Advanced & Expert Users Bash : While Loop behavior Post 302935030 by popeye on Thursday 12th of February 2015 12:11:29 PM
Old 02-12-2015
Bash : While Loop behavior
Good Morning

I think there may be something I dont understand fully.

The following code works well, but I dont like the set domen method.

Code:
#!/bin/bash
#
domen="y"
while [ "$domen" == "y" ]
do
echo " M A I N - M E N U"
echo "1. Contents of /etc/passwd"
echo "2. List of users currently logged"
echo "3. Prsent handling directory"
echo "4. Exit"
echo "Please enter option [1-4] : "
read theopt
echo $theopt
case $theopt in
1) echo $opt;;
2) echo $opt;;
3) echo $opt;;
4) exit 0;;
*) echo "Bad opt";;
esac
done


So I looked in one of my books (Written by Chris FA Johnson) and on the web for a second example. The following doesnt work. You'll have to run it to see what I mean. Ill try to explain. As I run through the menu options to test, at one point or another, my option isnt read and the behavior is kind of like a back space. Even when using -n1 for read behavior was odd.


Code:
#!/bin/bash
#
while : 
do
echo " M A I N - M E N U"
echo "1. Contents of /etc/passwd"
echo "2. List of users currently logged"
echo "3. Prsent handling directory"
echo "4. Exit"
echo "Please enter option [1-4] : "
read theopt
echo $theopt
case $theopt in
1) echo $opt;;
2) echo $opt;;
3) echo $opt;;
4) exit 0;;
*) echo "Bad opt";;
esac
done

Chris' example does provide a function to do the reading of the options, but I want to understand whats going on here.

As usual thanks for the help !
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Last edited by popeye; 02-12-2015 at 01:18 PM..
 

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LEARN ABOUT DEBIAN

ident2

ident2(8)						      System Manager's Manual							 ident2(8)

NAME

       ident2 - An advanced ident daemon

SYNOPSIS

       ident2 [options]

DESCRIPTION

       ident2 is an advanced ident daemon, which can run as an inetd service or on it's own. It has various features such as user defined and ran-
       dom replies, extensive logging, and full administrative control.

OPTIONS

       The program follows the usual GNU syntax command-line unless it is unsupported on your system. GNU options begin with two  dashes(`-')  and
       have much more descriptive names.

       -h, --help
	      Show summary of options.

       -u, --usage
	      Shows example command lines

       -v, --version
	      Show version information

       -l, --license
	      Show licensing information

       -a, --force-inetd
	      Force inetd mode, if autodetection isn't working.

       -d, --force-daemon
	      Force standalone daemon, if autodetection isn't working.

       -i, --use-user-ident
	      Allow user defined ident replies. Just do a echo 'ident ar' > ~/.ident to change your ident reply.

       -y, --user-reply-file
	      File ident2 should look for in user's homedir for replies. Default is ~/.ident

       -n, --allow-noident-file
	      Disable replies for user if user has a ~/.noident file. This behavior is disabled by default.

       -o, --client-timeout
	      Clients timeout after this many seconds

       -s, --dont-change-uid
	      Ident2  will  normally  try  to change it's uid to something less privileged if it finds it's uid to be 0. This option disables this
	      behavior altogether.

       -r, --always-random
	      Always send a random reply, regardless of what kind of request the client made. This is useful for abusing  the  ident  protocol	as
	      well as assisting outgoing IP masqueraded connections.

       -m, --daemon-maxclients
	      Daemon-only: Accept no more than this many connections at a time.

       -p, --daemon-port
	      Daemon-only: Bind this port, instead of 'auth' aka 113

       SEE ALSO
	      inetd(8), inetd.conf(5)

AUTHOR

       This manual page was written by Alexander Reelsen <ar@rhwd.net>, for the Debian GNU/Linux system (but may be used by others).

									GNU								 ident2(8)
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