Check if a package is installed. If it is, the version number will be shown.

dpkg -l python
If the first two letters are "ii", then the package is installed. You can also use wildcards. For example, . dpkg -l openoffice* . Note that dpkg will usually not report packages which are available but uninstalled. If you want to see both which versions are installed and which versions are available, use this command instead: . apt-cache policy python
Sample Output
Desired=Unknown/Install/Remove/Purge/Hold
| Status=Not/Inst/Conf-files/Unpacked/halF-conf/Half-inst/trig-aWait/Trig-pend
|/ Err?=(none)/Reinst-required (Status,Err: uppercase=bad)
||/ Name                                            Version                              Description
+++-===============================================-====================================-==============================================================================
ii  python                                          2.6.6-3+squeeze2                     interactive high-level object-oriented language (default version)

1
By: hackerb9
2011-01-05 06:15:13

2 Alternatives + Submit Alt

What Others Think

What the...? I submitted this command as a superior alternative to a positively ranked command and ended up voted negative with no comments as to why.
hackerb9 · 540 weeks and 3 days ago

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Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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