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Full Discussion: Hi im new to bash scripting I want to know what does the regex expression do ??
Top Forums Shell Programming and Scripting Hi im new to bash scripting I want to know what does the regex expression do ?? Post 302722319 by kevin298 on Friday 26th of October 2012 06:19:22 PM
Old 10-26-2012
Hi im new to bash scripting I want to know what does the regex expression do ??
# check host value regex='^([1-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])(\.([0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])){3}$' if [ "$(echo $host | grep '[A-Za-z]')" != "" ]; then if [[ "$(host $host)" =~ "not found" ]]; then echo host $host not found exit 4 fi elif [[ ! $host =~ $regex ]]; then echo $host is an invalid host address exit 5 fi
 

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LEARN ABOUT OPENDARWIN

innetgr

innetgr(1)							   NSS utilities							innetgr(1)

NAME

       innetgr - Check netgroup membership

SYNTAX

       innetgr [-d domain] [-h host] [-u user] [-v] <netgroup>

DESCRIPTION

       innetgr	checks if the specified user, host or domain is a member of the given netgroup. The program does not produce any output unless the
       verbose ( -v ) flag is given.

       The exit status is 0 if the user/host/doman combination is a member of the given netgroup.  Exit status is 1  if  the  combination  is  not
       found in the group, and 2 if one of the arguments are invalid.

OPTIONS

       --domain <domain> | -d <domain>
	      Search in the given domain.

       --host <host name> | -h <host name>
	      Search for the given host name.

       --user <user name> | -u <user name>
	      Search for the given user name.

       --verbose | -v
	      Enable verbose mode

       --version | -V
	      Show version information.

EXAMPLES

       To check if the current host is listed in the netgroup allhosts, use this command line:

       if innetgr -h `uname -n` allhosts ; then echo "Found"; fi

CONFORMING TO

       A innetgr program first appeared in NetBSD 1.4.

AUTHORS

       Petter Reinholdtsen <pere@hungry.com>

SEE ALSO

       getent(1) netgroup(1) innetgr(3) netgroup(5) nsswitch.conf(5)

Petter Reinholdtsen							0.7								innetgr(1)
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