Bash – How to check whether the pptpd package is installed and remove it

bashshell

I need to check whether the RPM package pptpd is installed, ignoring the version.
If it is I want to remove it. If not then check whether /etc/pptpd.conf and /etc/ppp/ exist. If yes for any or both then rm -rf.

Best Answer

rpm -q pptpd
if [ $? = 0 ]
then
echo "pptpd installed.. removing"
rpm -e pptp
elif [ -e "/etc/pptpd.conf" ]
then 
rm -rf /etc/pptpd.conf
fi

But I wonder if you need it removed checking for the existence package/file is needed ?

Related Solutions

Bash – Unique Features of bash compared to zsh

zsh is for vulcans. ;-)

Seriously: bash 4.0 has some features previously only found in zsh, like ** globbing:

% ls /usr/src/**/Makefile

is equivalent to:

% find /usr/src -name "Makefile"

but obviously more powerful.

In my experience bash's programmable completion performs a bit better than zsh's, at least for some cases (completing debian packages for aptitude for example).

bash has Alt + . to insert !$

zsh has expansion of all variables, so you can use e.g.



% rm !$<Tab>


for this. zsh can also expand a command in backtics, so

% cat `echo blubb | sed 's/u/a/'`<Tab>


yields

% cat blabb


I find it very useful to expand rm *, as you can see what would be removed and can maybe remove one or two files from the commmand to prevent them from being deleted.

Also nice: using the output from commands for other commands that do not read from stdin but expect a filename:

% diff <(sort foo) <(sort bar)


From what I read bash-completion also supports completing remote filenames over ssh if you use ssh-agent, which used to be a good reason to switch to zsh.

Aliases in zsh can be defined to work on the whole line instead of just at the beginning:

% alias -g ...="../.."
% cd ...

Bash – How to check in bash if a shell is running in interactive mode

According to man bash:

PS1 is set and $- includes i if bash is interactive, allowing a shell script or a startup file to test this state.

So you can use:

if [[ $- == *i* ]]
then
    do_interactive_stuff
fi

Also:

When an interactive shell that is not a login shell is started, bash reads and executes commands from /etc/bash.bashrc and ~/.bashrc, if these files exist.

So ~/.bashrc is only sourced for interactive shells. Sometimes, people source it from ~/.bash_profile or ~/.profile which is incorrect since it interferes with the expected behavior. If you want to simplify maintenance of code that is common, you should use a separate file to contain the common code and source it independently from both rc files.

It's best if there's no output to stdout from login rc files such as ~/.bash_profile or ~/.profile since it can interfere with the proper operation of rsync for example.

In any case, it's still a good idea to test for interactivity since incorrect configuration may exist.

Best Answer

Related Solutions

Bash – Unique Features of bash compared to zsh

Bash – How to check in bash if a shell is running in interactive mode

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