Questions[bourne-shell](server)

I'm making a script that installs MariaDB, and I'd like to set a root password. I've got the following in said script:

DEBIAN_FRONTEND=noninteractive

echo mariadb-server-10.0 mariadb-server-10.0/root_password password tmpsetup | debconf-set-selections
echo mariadb-server-10.0 mariadb-server-10.0/root_password_again password tmpsetup | debconf-set-selections
apt-get install -y mariadb-server

This doesn't seem to work, as I can't log into the root account with the "tmpsetup" password. What am I doing wrong?

I wish to append & sign to the end of particular command (say tkdiff) whenenver I execute the command.

Please let me know what kind of alias / any other solution should I create in bashrc.

Thanks in advance.

Note: I may have few arguments to the command which i execute. & should come at the end so that I can execute in b/g and I can use the shell for any other purpose.

If want to check if a process is running and start it if not. My script below is buggy and always says that a process is running. What is wrong?

$ ./check_n_run thisisnotrunning
./check_n_run: thisisnotrunning is already running

Here is the script:

$ cat check_n_run

#!/bin/sh

USAGE="usage: $0 processname"
if [ $# -ne 1 ] ; then
        echo "$USAGE" >&2
        exit 1
fi

ps ax | grep -v grep | grep $1> /dev/null
if [ $? -eq 1 ]
then
  echo "$1 not running"
  # start here      
else
  echo "$0: $1 is already running" >&2
fi

exit 0

what is the difference between braces and normal brackets in bash?

FYI... I did not get it in the related questions list and also not able to locate it in questions search. Please point me to the question if it has been already asked.

In a bourne shell script (#!/bin/sh) how can check to see if a remote NFS share is mounted and, if it is not, mount it? I've got an ugly set of cat, greps and ifs using the output of 'mount' at the moment but it doesn't seem to be doing a reliable job.