Hi,
I'm new to unix and got struck here.Can any one help me out.My question is ..
is the command

if [ ps -ef |grep "any pid"];
then
  echo "do some stuff"
fi

ps -ef | grep -q "any pid"
if [ $? -eq 0 ]
then
    echo "do some stuff"
fi

Thanks Balajesuri!!

Can you throw some light on the syntax too.. it would be helpfull.

ps -ef | grep -q "any pid" => Search for "any pid" from the output of ps -ef but don't display any output (-q takes care of this).
if [ $? -eq 0 ]            => $? is the exit status of last command executed. $? is set to 0 if the last command executed is a success.

suppose i want to grep only that PIDs which have its parrent pid as 1, then what should i do?

Something similar...

if  pgrep "some_pid" >/dev/null
then 
  echo "do some stuff"
fi

Thanks Ahamed!!

can you help me little more..
suppose we have a pid= 15641 and it PPID =1
i want to check if this process is there i'll do some stuff..
now how would i check