#!/bin/sh

# Valid environment variables to appear in a planetlab config file
TAGS='IP_METHOD HOST_NAME DOMAIN_NAME PROXY_SERVER
      IP_ADDRESS IP_GATEWAY IP_NETMASK IP_NETADDR IP_BROADCASTADDR 
      IP_DNS1 IP_DNS2 PRIMARY_DEV PRIMARY_MAC'

# Valid characters that variable can be set to
CHARS='[:alnum:]\.: _-'

REGEX=''

for t in $TAGS
do
    if [ "$REGEX" == "" ]
    then
        REGEX="^$t"
    else
        REGEX="$REGEX|^$t"
    fi
done
/bin/egrep "($REGEX)\=\\\"[$CHARS]*\\\"\s*$"