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.


    6
    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

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Add GPG key easy - oneliner
Replace KEY with GPG key. This command will load GPG key and add it to your system so you can use software from third party repos etc.

Install pip with Proxy
Installs pip packages defining a proxy

Show Shared Library Mappings
shows which shared lib files are pointed to by the dynamic linker.

Recursively find top 20 largest files (> 1MB) sort human readable format
Search for files and list the 20 largest. $ find . -type f gives us a list of file, recursively, starting from here (.) $ -print0 | xargs -0 du -h separate the names of files with NULL characters, so we're not confused by spaces then xargs run the du command to find their size (in human-readable form -- 64M not 64123456) $ | sort -hr use sort to arrange the list in size order. sort -h knows that 1M is bigger than 9K $ | head -20 finally only select the top twenty out of the list

Binary clock
Fun idea! This one adds seconds and keeps running on the same line. Perl's probably cheating though. :)

Change your timezone

throttle bandwidth with cstream
this bzips a folder and transfers it over the network to "host" at 777k bit/s. cstream can do a lot more, have a look http://www.cons.org/cracauer/cstream.html#usage for example: $ echo w00t, i'm 733+ | cstream -b1 -t2 hehe :)

Convert from octal format to umask
Umask is obtained subtracting 7 from each cypher of octal format. I store octal perm format in an array,then for each element of array I subtract 7. The result is the umask.

Scan Subnet for IP and MAC addresses

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" }


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