Commands by Flameeyes (7)

  • This is a quick replacement for lspci if you need to know what's in a given system but pciutils is not installed. You then need something that can look up the IDs from pci.ids if you want the verbose output. Show Sample Output


    4
    for device in /sys/bus/pci/devices/*; do echo "$(basename ${device} | cut -c '6-') $(cut -c '3-6' ${device}/class): $(cut -c '3-' ${device}/vendor):$(cut -c '3-' ${device}/device)"; done
    Flameeyes · 2012-04-13 03:26:02 0
  • This works in combination with http://www.commandlinefu.com/commands/view/10496/identify-exported-sonames-in-a-path as it reports the NEEDED entries present in the files within a given path. You can then compare it with the libraries that are exported to make sure that, when cross-building a firmware image, you're not bringing in dependencies from the build host. The short version of it as can be seen in the same output is scanelf -RBnq -F "+n#f" $1 | tr ',' '\n' | sort -u Show Sample Output


    1
    scanelf --nobanner --recursive --quiet --needed --format "+n#F" $1 | tr ',' '\n' | sort -u
    Flameeyes · 2012-03-29 18:30:45 0
  • This provides a list of shared object names (sonames) that are exported by a given tree. This is usually useful to make sure that a given required dependency (NEEDED entry) is present in a firmware image tree. The shorter (usable) version for it would be scanelf -RBSq -F "+S#f" But I used the verbose parameters in the command above, for explanation. Show Sample Output


    1
    scanelf --nobanner --recursive --quiet --soname --format "+S#f"
    Flameeyes · 2012-03-29 18:26:25 0
  • The command requires app-text/xmlstarlet but it otherwise self-contained. It extracts all the herds and all the maintainers' email for a given package and is what I'm using on the Tinderbox to make it easier for me to report bugs. Show Sample Output


    0
    xmlstarlet sel -t -m '/pkgmetadata/herd' -v . -n -t -m '/pkgmetadata/maintainer' -v email metadata.xml
    Flameeyes · 2010-08-09 22:37:19 0
  • This does almost the same thing as the original, but it runs the full backtrace for _all_ the threads, which is pretty important when reporting a crash for a multithreaded software, since more often than not, the signal handler is executed in a different thread than the crash happened.


    5
    gdb --batch --quiet -ex "thread apply all bt full" -ex "quit" ${exe} ${corefile}
    Flameeyes · 2010-07-06 14:49:03 1
  • The output is only partial because runtime dependencies should count in also commands executed via system() and libraries loaded with dlopen(), but at least it gives an idea of what a package directly links to. Note: this is meaningful *only* if you're using -Wl,--as-needed in your LDFLAGS, otherwise it'll bring you a bunch of false positives. Show Sample Output


    2
    qlist --exact "$pkg" | sudo scanelf --needed --quiet --format '%n#F' | tr ',' '\n' | sort -u | qfile --from -
    Flameeyes · 2010-07-06 14:39:15 0
  • Revised approach to and3k's version, using pipes and read rather than command substitution. This does not require fiddling with IFS when paths have whitespace, and does not risk hitting command-line size limits. It's less verbose on the missing files, but it stops iterating at the first file that's missing, so it should be definitely faster. I expanded all the qlist options to be more self-describing.


    3
    emerge -av1 `qlist --installed --nocolor | uniq | while read cp; do qlist --exact $cp | while read file; do test -e $file || { echo $cp; echo "$cp: missing $file (and maybe more)" 1>&2; break; }; done; done`
    Flameeyes · 2010-07-04 19:55:42 2

What's this?

commandlinefu.com is the place to record those command-line gems that you return to again and again. That way others can gain from your CLI wisdom and you from theirs too. All commands can be commented on, discussed and voted up or down.

Share Your Commands


Check These Out

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

check open ports without netstat or lsof

Rapidly invoke an editor to write a long, complex, or tricky command
Next time you are using your shell, try typing $ ctrl-x ctrl-e # in emacs mode or $ v # in vi mode The shell will take what you've written on the command line thus far and paste it into the editor specified by $EDITOR. Then you can edit at leisure using all the powerful macros and commands of vi, emacs, nano, or whatever.

List subfolders from largest to smallest with sizes in human readable form

Optimize Xsane PDFs
Xsane produces PDFs that are too large - particularly multipage PDFs. This command compresses them. If you do not use A4, remove the -sPAPERSIZE flag.

Copy a file and force owner/group/mode
This is useful when you want to copy a file and also force a user, a group and a mode for that file. Note: if you want to move that file instead of copying it, you can use $install -o user -g group -m 755 /path/to/file /path/to/dir/ && rm -f /path/to/file which will remove the file only if the install command went fine.

Upgrade pip-installed python packages

Display _something_ when an X app fails
When you run an X program from a terminal you can see any errors. But when it's run from another X program (eg from a menu item, from your fluxbox 'keys' file etc) it might just die and you see nothing (except perhaps in .xsession-errors). Instead, launch it via this command and you'll see the termination status, stderr and stdout. eg: "xlaunch firefox" or "xlaunch 'echo stdout; echo stderr >&2; false'": 'echo stdout; echo stderr >&2; false' failed with error 1 STDERR: stderr STDOUT: stdout

List of commands you use most often
Plot your most used commands with gnuplot.

Search and play MP3 from Skreemr
This use the Screemr search engine to play mp3 songs


Stay in the loop…

Follow the Tweets.

Every new command is wrapped in a tweet and posted to Twitter. Following the stream is a great way of staying abreast of the latest commands. For the more discerning, there are Twitter accounts for commands that get a minimum of 3 and 10 votes - that way only the great commands get tweeted.

» http://twitter.com/commandlinefu
» http://twitter.com/commandlinefu3
» http://twitter.com/commandlinefu10

Subscribe to the feeds.

Use your favourite RSS aggregator to stay in touch with the latest commands. There are feeds mirroring the 3 Twitter streams as well as for virtually every other subset (users, tags, functions,…):

Subscribe to the feed for: