Suppressing errors from command output

UNIX HP-UX
1

Hi,

When I run the command "print_manifest | grep "Main Memory", I get the note :

# /opt/ignite/bin/print_manifest | grep "Main Memory"
NOTE: Could not read the /etc/resolv.conf file.
    Main Memory:        196498 MB
#

How do I suppress the part :

NOTE: Could not read the /etc/resolv.conf file.

The file /etc/resolv.conf does not exist in the server, because we do not use DNS for our hostname resolution. However, this NOTE does not pop once I create the resolv.conf file. But is this a good solution?

Please advise.

2

Did you consider redirecting stderr to /dev/null ?

3

Hi,

The script expects to see the resolve.conf file, so is correctly identifying the missing file - touching the file removes the error.

There are a number of options, the simplest is probably to do;

touch /etc/resolv.conf
chmod 440 /etc/resolv.conf

Alternatively you could send the stderr to /dev/null

Your final option would be to modify the script and put the offendin part of the script inside a test condition - running if the resolv.conf file exists.

Regards

Gull04

1 Like
4

I tried these methods to redirect stderr to /dev/null, and still that message pops :

$ sudo print_manifest | grep "Main Memory" > /dev/null 2>&1
NOTE: Could not read the /etc/resolv.conf file.
$ sudo print_manifest | grep "Main Memory" &>/dev/null
[1]     7684
$ NOTE: Could not read the /etc/resolv.conf file.
    Main Memory:        196498 MB

Are the commands I am using above correct?
If so, then seems like redirecting the error wont work. Need to touch the file?

5

You are piping the command's stdout to grep and then redirecting grep 's stderr to the null device. Where does the command's stderr go to?

EDIT: Alternatively, make it all a "compound command":