Need urgent help on exit status of the script

Shell Programming and Scripting
1

Guys,
I am writing a script that executes a series of commands with a function like:

_Command "ps -ef | grep java"
_Command "vmstat"
_Command "llll"

Even if one of these commands fail, my script should exit with non-zero code i.e 16.
If all commands are successful, my script should exit with 0.

My action for this requirement :
I am collecting return codes of all commands into a variable and grepping for a non-zero string in that variable. If it is found I am exiting the script with 16 otherwise exit the script with 0.But , my code is not working in case the variable is having all zeros' .

example:

sriram] var="0 0 0 0"
sriram] echo $var | grep -qv 0
sriram] $?
ksh: 1:  not found.
sriram] var="0 0 0 127"
sriram] echo $var | grep -qv 0
sriram] $?
ksh: 1:  not found.

In both cases grep is returning 1.
If it var contains all zeros, then my script should exit with 0.

This is my actual script:

#Command execution function
_Command()
{
   _Report "BEGIN Command : $@ "
    #Executing command and redirecting stderr to devnull
    output=$(eval $@)
    #Exit status of the command
    stat=$?
    echo $output
    echo "++ $stat ++"

    if [[ $stat -ne 0 ]] ; then
        #collecting all return codes of commands into a variable
                Returns=$Returns" "$stat
        _Report "$@ not successful"
        _Report "END"
    else
                Returns=$Returns" "$stat
        _Log "$output"
        _Report "END"
    fi
}

#List of commands to be run for unix swap space problem

        _Report "##  memory size used by each of the running processes ##"
        _Command 'ps -eo vsz,pid,args | sort -n'

    _Report "## memory that is locked but not used ##"
    _Command 'ipcs -ma | grep -w -E "0|NATTCH" '

        _Report "## Check for virtual memory statistics ##"
        _Command "vmstat"

        _Command "ps -ef | grep micro"


#Search for nonzero code in all the exitcodes of commands
echo $Returns
echo $Returns | grep -qv 0

#If one of the commands fail, autocheck script will return 16
[ $? = 1 ] && exit $Error || exit $Success

Please help or suggest any alternatives...
Many thanks in advance,

Sriram:wall:

2 
var="0 0 0 0"
echo $var | grep -q "0 0 0 0"
echo $?
0

var="0 0 0 127"
echo $var | grep -q "0 0 0 0"
echo $?
1

var="0 0 0 0"
echo $var | grep -qv "0 0 0 0"
echo $?
1

var="0 0 0 127"
echo $var | grep -qv "0 0 0 0"
echo $?
0

you missed echo in your testing
-v is for invert selection

--ahamed

3

thanks ahmed,

but i cannot hard "0 0 0 0".... as i can run even 10 commands in the same script..
so i have to grep for non-zero exit codes.

Thanks,

Sriram:confused:

4

Just add a flag variable and change right after a command fails.
At the end just check if that variable value has changed from the beginning:

_flag=0
...
command  ... || _flag=16
...
command ... || _flag=16
....
exit $_flag
1 Like
5 
echo $var | sed 's/0//g' | grep -qv 0; echo $?

Not sure if it is the best solution. But it will serve the purpose I guess.
Even if you have 0 in a non-zeo exit code, it shouldn't be a problem.

--ahamed

1 Like
6

thanks ahamed and rod... both solutions work.. however i got another idea just now...

I am not collecting succesful commands, instead i am collecting only non-zero codes...
so, i f all commands are succesful, $var contains " " or $var contains "127 ".

So, I wrote this to handle, it is working not efficient though, am i right:

my $var contains either var=" 127 255" or var=" "..

#If one of the commands fail, autocheck script will return 16
if  $var 2>/dev/null ; then
   exit $Success
else
   exit $Error
fi
7

Alternatively, he could have grepped for a non-zero digit. Although, if each individual exit status is not required, radoulov's suggestion is probably best. And since it seems that the command sequence is known at "compile" time, there's really no need for eval.

Regards,
Alister

---------- Post updated at 11:05 AM ---------- Previous update was at 11:02 AM ----------

That won't work at all. You need to use test/[.

Regards,
Alister

1 Like
8

Hi Alister,
I have to collect command output and see the exit status at the same time.
Can this work with rad's suggestion?

Regards,

Sriram

---------- Post updated at 09:02 PM ---------- Previous update was at 08:40 PM ----------

with out eval if i use output=$(cmd) , it breaks if there exists pipe in the command like ps -ef | grep "defunct" ..

only single word commans work like vmstat etc...

One more think Alister, how to use my if condition with test ?

Thanks,

Sriram