The apt command: Combining apt-get and apt-cache and adds a progress bar (2014)

Post by creshal » Sat, Mar 05, 2016, 9:23 PM UTC

miken123 wrote: post #52

currysausage wrote: post #30

Earlier quoted context omitted.

"aptitude [...] is a friendly frontend to apt." "The primary command line tool is aptitude. apt-get fulfills a similar purpose and although it is no longer the recommended primary tool some still use it." If you prefer the apt-* commands: "You can also use Wajig, for an unified and more logical command-line interface to all package management functions." (Apparently, apt is the new Wajig, except that apt doesn't auto…

Yeah, until you do an upgrade: "The upgrade process for some previous releases recommended the use of aptitude for the upgrade. This tool is not recommended for upgrades from wheezy to jessie." See https://www.debian.org/releases/stable/amd64/release-notes/c...

Post by clebio » Sat, Mar 05, 2016, 10:13 PM UTC

josho wrote: post #60

clebio wrote: post #27

Earlier quoted context omitted.

I can't answer specifically for `apt`, but many commands take significantly longer if you let them display to stdout versus piping their output to a file or `/dev/null`. cf.: $ time ls -R /usr real 0m7.570s user 0m0.104s sys 0m2.286s $ time ls -R /usr > /dev/null real 0m0.193s user 0m0.036s sys 0m0.154s (edit: when will I grok HN markup?? cough support markdown cough )

I've always assumed something like the above is slow due to the terminal blocking the program to perform updates to the display. Whereas a status indicator isn't exactly pushing much data to the terminal. So, It shouldn't impact run time.

Post by vacri » Sat, Mar 05, 2016, 11:46 PM UTC

jasonjayr wrote: post #28

clebio wrote: post #27

Earlier quoted context omitted.

I can't answer specifically for `apt`, but many commands take significantly longer if you let them display to stdout versus piping their output to a file or `/dev/null`. cf.: $ time ls -R /usr real 0m7.570s user 0m0.104s sys 0m2.286s $ time ls -R /usr > /dev/null real 0m0.193s user 0m0.036s sys 0m0.154s (edit: when will I grok HN markup?? cough support markdown cough )

Did you run those two commands in sequence? Did you account for disk-cache effects? Try running it 4 times, alternating the versions and see what your last 2 times are ...

    # all the below run in the same MATE desktop
    # lxterm (from lxde - is easiest on my eye)
    $ time ls -R /usr
    real    0m19.974s
    user    0m0.860s
    sys	    0m0.832s

    # gnome terminal
    $ time ls -R /usr
    real    0m19.902s
    user    0m0.800s
    sys     0m0.776s

    # xterm (yes, it really is 10x the speed)
    $ time ls -R /usr
    real    0m1.872s
    user    0m0.856s
    sys     0m0.800s

    # rerun in the first terminal, and the time hasn't changed - still 19s

    # now in lxterm redirecting to null
    # (and xterm gives similar results here)
    $ time ls -R /usr > /dev/null

    real    0m0.418s
    user    0m0.256s
    sys     0m0.156s

Post by matt_wulfeck » Sun, Mar 06, 2016, 6:02 AM UTC

iam-TJ wrote: post #38

matt_wulfeck wrote: post #25

Earlier quoted context omitted.

I have this problem too. If I did myself shelling out to grep with pcre flags to find a simple library then there's a UX issue.

Search uses regular expressions so generally no need for grep unless you need more complex filters; --names-only has the -n short-form: apt-cache search -n More generally apt-get and apt-cache are designed to be backward-compatible for use in scripts whereas apt is not[0]: SCRIPT USAGE AND DIFFERENCES FROM OTHER APT TOOLS The apt(8) commandline is designed as an end-user tool and it may change behavior between versio…

Post by konfou » Sun, Mar 06, 2016, 11:22 AM UTC

krylon wrote: post #68

adricnet wrote: post #11

Earlier quoted context omitted.

Only one of them requires readwrite system administrator privileges (eg sudo). apt-cache can be run by any user as it doesn't expose any secret data and can't be used to make changes. apt-get can install and uninstall software as well as download packages and thus needs root privileges in the classic UNIX model.

On CentOS, I can do "yum search something" as a regular user, while "yum install something" or "yum upgrade" require root privileges. I think it's similar with the pkg command on FreeBSD.