<div>
You could use below command sequence: 
 
HWADDR=$( . /etc/sysconfig/network-scripts/ifcfg-eth0 ; echo $HWADDR)
</div>

<div>
Hi PJ, 
 
I think noci's quite elegant solution will work if ifcfg-eth0 contains nothing which causes ifcfg-eth0 not to execute as a script (since he runs it as one). &nbsp;His solution will also set any other environment variables assigned in the ifcfg-eth0 file. &nbsp;If that's not good for you, here's an alternative way to do it: 
 
==&gt; ifcfg-eth0 &lt;== 
HWADDR=01:23:45:67:89 
anything else 
 
==&gt; gatherdata &lt;== 
#!/bin/bash 
HWADDR=$(perl -ne 'print $1 if /^HWADDR=(..:..:..:..:..)$/' ifcfg-eth0) 
echo &quot;HWADDR = '$HWADDR'&quot; 
 
Here's how it runs: 
$ ./gatherdata 
HWADDR = '01:23:45:67:89'
</div>

<div>
Thanks noci, 
I guess that will be fine then, and I think I was mistaken where I said your &quot;solution will also set any other environment variables assigned in the ifcfg-eth0 file&quot;, because the assignments will be done in a $(sub-shell), so will be forgotten immediately. 
Nice work! 
 
Question for noci: Is it possible for there to be any spaces (or other strange characters) in the assignments in the ifcfg-eth0 file, which might make it crash? &nbsp;For example, this would fail: 
VARIABLE=123 456
</div>

<div>
There might be spaces &nbsp;before variable names, or after the value, as these files are mostly genereated during system setup there mostly are no spaces... 
Here is an example: 
 

<pre><code class="code-1 nolinks" id="code-20-42491970-1">DEVICE=eth0
TYPE=&quot;Ethernet&quot;
ONBOOT=&quot;yes&quot;
USERCTL=&quot;no&quot;
BOOTPROTO=&quot;static&quot;
IPADDR=&quot;192.168.1.235&quot;
NETMASK=&quot;255.255.255.0&quot;
HWADDR=&quot;00:15:5d:01:16:35&quot;
</code></pre>
 
In this one no trailing spaces, usage in ifup: 
ifup call ifup-eth which does: 

<pre><code class="code-1 nolinks" id="code-20-42491970-2">....
CONFIG=${1}

need_config &quot;${CONFIG}&quot;

source_config
....
</code></pre>
 
 
Source config is somewhat more complex: 

<pre><code class="code-10 nolinks" id="code-20-42491970-3">source_config ()
{
 CONFIG=${CONFIG##*/}
 DEVNAME=${CONFIG##ifcfg-}
 . /etc/sysconfig/network-scripts/$CONFIG
 [ -r &quot;keys-$DEVNAME&quot; ] &amp;&amp; . /etc/sysconfig/network-scripts/keys-$DEVNAME
 case &quot;$TYPE&quot; in
 Ethernet)
 DEVICETYPE=&quot;eth&quot;
 ;;
 CIPE)
 DEVICETYPE=&quot;cipcb&quot;
 ;;
 IPSEC)
 DEVICETYPE=&quot;ipsec&quot;
 ;;
 Modem)
 DEVICETYPE=&quot;ppp&quot;
 ;;
 xDSL)
 DEVICETYPE=&quot;ppp&quot;
 ;;
 ISDN)
 DEVICETYPE=&quot;ippp&quot;
 ;;
 Wireless)
 DEVICETYPE=&quot;eth&quot;
 ;;
 &quot;Token Ring&quot;)
 DEVICETYPE=&quot;eth&quot;
 ;;
 CTC)
 DEVICETYPE=&quot;ctc&quot;
 ;;
 GRE | IPIP | IPIP6)
 DEVICETYPE=&quot;tunnel&quot;
 ;;
 SIT | sit)
 DEVICETYPE=&quot;sit&quot;
 ;;
 InfiniBand | infiniband)
 DEVICETYPE=&quot;ib&quot;
 ;;
 OVS*)
 DEVICETYPE=&quot;ovs&quot;
 ;;
 esac
 if [ -n &quot;$HWADDR&quot; ]; then
 HWADDR=$(echo $HWADDR | awk '{ print toupper($0) }')
 fi
 if [ -n &quot;$MACADDR&quot; ]; then
 MACADDR=$(echo $MACADDR | awk '{ print toupper($0) }')
 fi
 [ -z &quot;$DEVICE&quot; -a -n &quot;$HWADDR&quot; ] &amp;&amp; DEVICE=$(get_device_by_hwaddr $HWADDR)
 [ -z &quot;$DEVICETYPE&quot; ] &amp;&amp; DEVICETYPE=$(echo ${DEVICE} | sed &quot;s/[0-9]*$//&quot;)
 [ -z &quot;$REALDEVICE&quot; -a -n &quot;$PARENTDEVICE&quot; ] &amp;&amp; REALDEVICE=$PARENTDEVICE
 [ -z &quot;$REALDEVICE&quot; ] &amp;&amp; REALDEVICE=${DEVICE%%:*}
 [ -z &quot;$SYSCTLDEVICE&quot; ] &amp;&amp; SYSCTLDEVICE=${REALDEVICE/.//}
 if [ &quot;${DEVICE}&quot; != &quot;${REALDEVICE}&quot; ]; then
 ISALIAS=yes
 else
 ISALIAS=no
 fi
 if is_nm_running &amp;&amp; [ &quot;$REALDEVICE&quot; != &quot;lo&quot; ] ; then
 nm_con_load &quot;$CONFIG&quot;
 if ! is_false $NM_CONTROLLED; then
 UUID=$(get_uuid_by_config $CONFIG)
 [ -n &quot;$UUID&quot; ] &amp;&amp; _use_nm=true
 fi
 fi
}
</code></pre>
</div>

<div>
Hi noci &amp;&nbsp;tel2 
 
Thank you for taking the time to help, really appreciate it 
 
@noci, I've just tried your suggestion. First I had to make ifcfg-eth0 executable. 
Then I tried the following 
 
HWADDR=&quot;&quot; 
HWADDR=$( &nbsp;/etc/sysconfig/network-scripts/ifcfg-eth0 ; echo $HWADDR) 
echo &quot;$HWADDR&quot; 
 
I had to remove the dot in-front of the path name to find the file 
I seem to be getting an empty variable as I'm seeing a blank line when I echo &quot;$HWADDR&quot; 
 
Any ideas?
</div>

<div>
@ noci 
 
just tried HWADDR=$( &nbsp;grep HWADDR= &nbsp;/etc/sysconfig/network-scripts/ifcfg-eth0 | &nbsp;sed 's/^HWADDR=//' ) 
 
and that worked a treat, thank you very much
</div>

<div>
Eh. you DONT need to set the script executable. is it SHOULD not be executed but read. 
 
 
you missed the '.' &nbsp;space &nbsp; isn't './etc...' but '.' SPACE '/etc/....' 
before the script name wich means 'source' . 
&nbsp;(read the file, not execute the file). The FIRST DOES work is might be slightly more effective. 
 
It could be rewritten as: 
 
HWADDR=$( source /etc/sysconfig/network-scripts/ifcfg-eth0 ; echo $HWADDR)
</div>

<div>
<div class="content wysiwyg-content">
In a file called ifcfg-eth0 there is a line which states HWADDR=XX:XX:XX:XX:XX 
 
I have a script called &quot;gatherdata&quot; and have set a variable called &quot;HWADDR&quot; and I want the variable to be set to XX:XX:XX:XX:XX 
 
Is there an easy way of doing this? ive had a look on google and have seen the source command but couldn't find a good example to fit my scenario. 
 
Im on CentOS 6.8 
 
Thanks
</div>
</div>

In a file called ifcfg-eth0 there is a line which states HWADDR=XX:XX:XX:XX:XX

I have a script called "gatherdata" and have set a variable called "HWADDR" and I want the variable to be set to XX:XX:XX:XX:XX

Is there an easy way of doing this? ive had a look on google and have seen the source command but couldn't find a good example to fit my scenario.

Im on CentOS 6.8 

Thanks

Is it possible to read a variable from a file and use in a Sh script

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