翻译强力驱动I'm working on a Ubuntu system and currently this is what I'm doing:
if ! which command > /dev/null; then echo -e "Command not found! Install? (y/n) \c" read if "$REPLY" = "y"; then sudo apt-get install command fi fiIs this what most people would do? Or is there a more elegant solution?
To check if packagename was installed, type:
dpkg -s You can also use dpkg-query that has a neater output for your purpose, and accepts wild cards, too.
dpkg-query -l To find what package owns the command, try:
dpkg -S `which For further details, see article Find out if package is installed in Linux and dpkg cheat sheet.
To be a little more explicit, here's a bit of bash script that checks for a package and installs it if required. Of course, you can do other things upon finding that the package is missing, such as simply exiting with an error code.
PKG_OK=$(dpkg-query -W --showformat='${Status}\n' the.package.name|grep "install ok installed") echo Checking for somelib: $PKG_OK if [ "" == "$PKG_OK" ]; then echo "No somelib. Setting up somelib." sudo apt-get --force-yes --yes install the.package.name fiIf the script runs within a GUI (e.g. it is a Nautilus script), you'll probably want to replace the 'sudo' invocation with a 'gksudo' one.
This one-liner returns 1 (installed) or 0 (not installed) for the 'nano' package..
$(dpkg-query -W -f='${Status}' nano 2>/dev/null | grep -c "ok installed")even if the package does not exist / is not available.
The example below installs the 'nano' package if it is not installed..
if [ $(dpkg-query -W -f='${Status}' nano 2>/dev/null | grep -c "ok installed") -eq 0 ]; then apt-get install nano; fiI offer this update since Ubuntu added its "Personal Package Archive" (PPA) just as this question was answered, and PPA packages have a different result.
Native Debian repository package not installed:
~$ dpkg-query -l apache-perl ~$ echo $? 1PPA package registered on host and installed:
~$ dpkg-query -l libreoffice ~$ echo $? 0PPA package registered on host but not installed:
~$ dpkg-query -l domy-ce ~$ echo $? 0 ~$ sudo apt-get remove domy-ce [sudo] password for user: Reading package lists... Done Building dependency tree Reading state information... Done Package domy-ce is not installed, so not removed 0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.Also posted on: https://superuser.com/questions/427318/test-if-a-package-is-installed-in-apt/427898
UpAndAdam wrote:
However you can't simply rely on return codes here for scripting
In my experience you can rely on dkpg's exit codes.
The return code of dpkg -s is 0 if the package is installed and 1 if it's not, so the simplest solution I found was:
dpkg -s 2>/dev/null >/dev/null || sudo apt-get -y install Works fine for me...
This seems to work pretty well.
$ sudo dpkg-query -l | grep | wc -l 0 if not installed or some number > 0 if installed.I've found all solutions above can produce a false positive if a package is installed and then removed yet the installation package remains on the system.
To replicate: Install package apt-get install curl
Remove package apt-get remove curl
Now test above answers.
The following command seems to solve this condition:dpkg-query -W -f='${Status}\n' curl | head -n1 | awk '{print $3;}' | grep -q '^installed$'
This will result in a definitive installed or not-installed
$name="rsync" [ `which $name` ] $$ echo "$name : installed" || sudo apt-get install -y $nameThis will do it. apt-get install is idempotent.
sudo apt-get install commandThis feature already exists in Ubuntu and Debian, in the command-not-found package.
Use:
apt-cache policy If it is not installed, it will show:
Installed: noneOtherwise it will show:
Installed: versionapt list [packagename]seems to be the simplest way to do it outside of dpkg and older apt-* tools
which -y install This command is the most memorable:
dpkg --get-selections If it's installed it prints:
install
Otherwise it prints
No packages found matching
.
This was tested on Ubuntu 12.04.1 (Precise Pangolin).
For Ubuntu, apt provides a fairly decent way to do this. Below is an example for google chrome:
if apt -qq list google-chrome-stable 2>/dev/null | grep -q installed ; then apt-get install google-chrome-stable fiI'm redirecting error output to null because apt warns against using its "unstable cli". I suspect list package is stable so I think it's ok to throw this warning away. The -qq makes apt super quiet.
I've settled on one based on Nultyi's answer:
MISSING=$(dpkg --get-selections $PACKAGES 2>&1 | grep -v 'install$' | awk '{ print $6 }') # Optional check here to skip bothering with apt-get if $MISSING is empty sudo apt-get install $MISSINGBasically, the error message from dpkg --get-selections is far easier to parse than most of the others, because it doesn't include statuses like "deinstall". It also can check multiple packages simultaneously, something you can't do with just error codes.
Explanation/example:
$ dpkg --get-selections python3-venv python3-dev screen build-essential jq dpkg: no packages found matching python3-venv dpkg: no packages found matching python3-dev screen install build-essential install dpkg: no packages found matching jqSo grep removes installed packages from the list, and awk pulls the package names out from the error message, resulting in MISSING='python3-venv python3-dev jq', which can be trivially inserted into an install command.
I'm not blindly issuing an apt-get install $PACKAGES because as mentioned in the comments, this can unexpectedly upgrade packages you weren't planning on; not really a good idea for automated processes that are expected to be stable.