Commands by mhs (29)

  • Monitor all DNS queries made by Firefox


    2
    NSPR_LOG_MODULES=nsHostResolver:5 NSPR_LOG_FILE=/tmp/log.txt firefox
    mhs · 2015-09-30 01:56:36 10
  • Monitor all DNS queries seen by the local machine


    1
    dnstop -l 3 enp1s0f0
    mhs · 2015-09-30 01:55:11 9
  • Convert SWF to video

    This will dump a raw BGRA pixel stream and WAV which must then be converted to video: ffmpeg -f rawvideo -c:v rawvideo -s 1280x720 -r 12 -pix_fmt bgra -i "${i%.*}".bgra -c:v libx264 -preset veryslow -qp 0 -movflags +faststart -i "${i%.*}".wav -c:a libfdk_aac -b:a 384k "${i%.*}".mp4 ; rm "${i%.*}".bgra "${i%.*}".wav Our example generates an x264/720p/12fps/AAC best-quality MP4. To get dump-gnash, first install the build-dependencies for gnash (this step is OS-specific). Then: git clone http://git.savannah.gnu.org/r/gnash.git ; cd gnash ; ./autogen.sh ; ./configure --enable-renderer=agg --enable-gui=dump --disable-menus --enable-media=ffmpeg --disable-jemalloc ; make


    0
    i=in.swf; dump-gnash -1 -j 1280 -k 720 -D "${i%.*}".bgra@12 -A "${i%.*}".wav "${i}"
    mhs · 2015-05-06 23:52:39 28
  • Find which fibre HBA a disk is connected to

    Useful for big systems with lots of cards. (Update: does not work with USB disks)


    0
    udevadm info -q all -n /dev/sdc | grep ID_PATH | cut -d'-' -f 2 | xargs -n 1 lspci -s
    mhs · 2015-01-27 15:34:02 10
  • Generate map of your hardware


    2
    lstopo -p -v --whole-system --whole-io output.svg
    mhs · 2015-01-27 15:16:54 10
  • Map the slot of an I/O card to its PCI bus address

    Recent hardware may or may not enumerate *both of* these values


    1
    dmidecode --type 9 |egrep 'Bus Address|Designation'
    mhs · 2015-01-27 15:13:59 9
  • Aptitude pattern match

    Could be dangerous, if you have many packages all beginning with 'foo' or 'bar'. This will easily remove them all from your system.


    1
    aptitude --purge remove ~i^foo ~i^bar
    mhs · 2015-01-27 15:00:48 13
  • Nice beep


    1
    xset b 50 1700 10
    mhs · 2015-01-27 14:38:58 9
  • Performance tip: compress /usr/

    Periodically run the one-liner above if/when there are significant changes to the files in /usr/ = Before rebooting, add following to /etc/fstab : = /squashed/usr/usr.sfs /squashed/usr/ro squashfs loop,ro 0 0 usr /usr aufs udba=reval,br:/squashed/usr/rw:/squashed/usr/ro 0 0 No need to delete original /usr/ ! (unless you don't care about recovery). Also AuFS does not work with XFS


    4
    [ ! -d /squashed/usr ] && mkdir -p /squashed/usr/{ro,rw} ; mksquashfs /usr /squashed/usr/usr.sfs.new -b 65536 ; mv /squashed/usr/usr.sfs.new /squashed/usr/usr.sfs ; reboot
    mhs · 2014-05-10 06:01:06 10
  • Increase SCT of external USB disk enclosure to one hour.

    So I had this 2TB Seagate external disk/USB enclosure which by default would spin-down its internal drive (it enters a standby mode) after four minutes of inactivity.. Spinning-up the inactive drive was an annoying delay when accessing files and also it severely interfered with NFS.. SCT stands for "Standby Condition Timer". To completely disable SCT: sdparm --clear STANDBY -6 /dev/sdb To return to original (default) SCT settings: sdparm -D -p 0x1a -6 /dev/sdb To verify the settings (before and after): sdparm -a /dev/sdb No need for vendor-provided MSWIN tools, etc.


    2
    sdparm -s SCT=36000 --save /dev/sdb
    mhs · 2013-04-19 13:26:18 6
  • Limit the cpu usage of a process

    Similar to `cpulimit`, although `prlimit` can be found shipped with recent util-linux. Example: limit CPU consumption to 10% for a math problem which ordinarily takes up 100% CPU: Before: bc -l <(echo "1234123412341234^12341234") See the difference `prlimit` makes: prlimit --cpu=10 bc -l <(echo "1234123412341234^12341234") To actually monitor the CPU usage, use `top`, `sar`, etc.. or: pidstat -C 'bc' -hur -p ALL 1


    4
    prlimit --cpu=10 sort -u hugefile
    mhs · 2013-02-27 15:59:11 8
  • Commandline document conversion with Libreoffice

    In this example, the docx gets converted to Open Document .odt format. For other formats, you'll need to specify the correct filter (Hint: see "Comments" link below for a nice list).


    15
    soffice --headless -convert-to odt:"writer8" somefile.docx
    mhs · 2012-12-27 15:08:38 34
  • Android PNG screenshot

    Works with *rooted* Android devices. 400x800 are the screen dimensions of a typical handheld smartphone.


    8
    adb pull /dev/graphics/fb0 /dev/stdout | ffmpeg -vframes 1 -vcodec rawvideo -f rawvideo -pix_fmt rgb32 -s 480x800 -i pipe:0 -f image2 -vcodec png screenshot.png
    mhs · 2012-12-26 13:21:18 25
  • Dump android contacts, sms

    Crude, but works. Note for security, /data/ will be inaccessible unless your device has been *rooted*. On the other hand, if a device has been rooted, its data is now wide open to anyone with a USB cable and the above "one-liner". `adb` is one of the platform tools in the android SDK. To get SMS messages: adb pull /data/data/com.android.providers.telephony/databases/mmssms.db ; sqlite3 -batch <<EOF contacts2.db <CR> .header on <CR> .mode tabs <CR> select * from sms; <CR> EOF


    2
    adb pull /data/data/com.android.providers.contacts/databases/contacts2.db ; sqlite3 -batch <<EOF contacts2.db <CR> .header on <CR> .mode tabs <CR> select * from data; <CR> EOF
    mhs · 2012-12-26 11:35:23 22
  • wget multiple files (or mirror) from NTLM-protected Sharepoint

    If you have to deal with MS Sharepoint which is (rarely, let's hope) used in e.g. certain corporate environments). This uses Cntlm. For single files, just use cURL -- its NTLM authentication works quite well. # /etc/cntlm.conf: # Username account # Domain domain # Password ############ # Proxy 10.20.30.40 (IP of the sharepoint site) # NoProxy * # Listen 3128


    1
    http_proxy=http://127.0.0.1:3128 wget --http-user='domain\account' --http-password='###' -p -r -l 8 --no-remove-listing -P . 'http://sp.corp.com/teams/Team/Shared%20Documents/Forms/AllItems.aspx?RootFolder=%2fteams%2fTeam%2fShared%20Documents%2fFolder'
    mhs · 2012-12-26 09:03:55 5
  • Serial console to a Vmware VM

    Create a serial console with "socket (named pipe)" of "/tmp/socket", "from:server, to:virtual machine" in vmware player, etc.. gui. Run the above command after you have booted the guest OS (which should also be configured for serial console).


    1
    socat unix-connect:/tmp/socket stdio,echo=0,raw
    mhs · 2012-12-19 07:58:09 9
  • parted - scripted partitioning (of all multipathed SAN LUNs)

    `multipath -ll` requires Device Mapper multipath.conf configuration. And of course, replace "3PARdata,VV" with your disk array's SCSI vendor,LUN name. - GPT partition table allows you to create >2TB partitions


    1
    for i in $(multipath -ll | grep "3PARdata,VV"|awk '{print $1}') ; do parted -a optimal /dev/mapper/$i --script -- mklabel gpt mkpart primary 1 -1 set 1 lvm on ; done
    mhs · 2012-09-12 15:30:36 8
  • Formatted list - WWNs of all LUNs

    Use `scsi_id` to positively identify which LUNs are which (i.e. compare with the list of LUNs you created on your disk array) (shown: RHEL5 usage) Debian usage: # for i in /dev/sd* ; do wwn=`/lib/udev/scsi_id -g --device $i` ; [ "$wwn" != "" ] && echo -e ${i##*/}'\t'$wwn ;done Show Sample Output


    1
    for i in /sys/block/sd* ; do wwn=`/lib/udev/scsi_id -g -s /block/${i##*/}` ; [ "$wwn" != "" ] && echo -e ${i##*/}'\t'$wwn ;done
    mhs · 2012-09-12 14:14:53 5
  • detect partitions

    `blkid` is an interface to libuuid - it can read Device Mapper, EVMS, LVM, MD, and regular block devices. -c /dev/null - Do not use cached output from /etc/blkid.tab or /etc/blkid/blkid.tab (RHEL) -i - Display I/O Limits (aka I/O topology) information (not available in RHEL) -p - Low-level superblock probing mode (not available in RHEL) Show Sample Output


    2
    blkid -c /dev/null
    mhs · 2012-09-12 13:34:41 8
  • Keep a copy of the raw Youtube FLV,MP4,etc stored in /tmp/

    Certain Flash video players (e.g. Youtube) write their video streams to disk in /tmp/ , but the files are unlinked. i.e. the player creates the file and then immediately deletes the filename (unlinking files in this way makes it hard to find them, and/or ensures their cleanup if the browser or plugin should crash etc.) But as long as the flash plugin's process runs, a file descriptor remains in its /proc/ hierarchy, from which we (and the player) still have access to the file. The method above worked nicely for me when I had 50 tabs open with Youtube videos and didn't want to have to re-download them all with some tool.


    8
    lsof -n -P|grep FlashXX|awk '{ print "/proc/" $2 "/fd/" substr($4, 1, length($4)-1) }'|while read f;do newname=$(exiftool -FileModifyDate -FileType -t -d %Y%m%d%H%M%S $f|cut -f2|tr '\n' '.'|sed 's/\.$//');echo "$f -> $newname";cp $f ~/Vids/$newname;done
    mhs · 2012-02-25 01:49:45 6
  • Hide the name of a process listed in the `ps` output

    exec -a $NAME $COMMAND $ARGS `your_cmd -erase_all_files` is the real process, but harmless-looking getty appears in the process table. Never actually had a need to do this, but interesting nonetheless... Tested in bash, dash. -a $NAME "pass NAME as the zeroth argument to COMMAND", i.e. customise the name of the process (as commonly seen with `ps`) Show Sample Output


    16
    exec -a "/sbin/getty 38400 tty7" your_cmd -erase_all_files
    mhs · 2012-02-01 10:54:03 9
  • Show 'Hardware path'-style tree of all devices in Linux

    Show Sample Output


    6
    lshw -short
    mhs · 2011-06-28 23:32:30 10
  • Find out the starting directory of a script

    Invoked from within a shell script, this will print the directory in which the script resides. Doesn't depend on external tools, /proc/self/*, etc.. (`echo` is a shell builtin.) To see the *current working* directory of a script, use `pwd`.


    13
    echo "${0%/*}"
    mhs · 2011-04-17 12:09:56 13
  • move messages directly from one IMAP inbox to another

    This one-liner was useful in helping someone I know to get off of MS Exchange. `mailutil` proved to be a much better alternative than `fetchmail` or `getmail` in this case. It quickly moved all mails to the destination server (a simple Dovecot/Maildir setup), with no need to convert back and forth between mbox/maildir on the user's own system.


    2
    mailutil appenddelete '{src.mailsrv1.com:993/imap/norsh/notls/ssl/novalidate-cert/user="username"}INBOX' '{dest.mailsrv2.com:143/imap/norsh/notls/user="username"}INBOX'
    mhs · 2011-02-08 09:37:05 4
  • Stop Flash from tracking everything you do.

    Brute force way to block all LSO cookies on a Linux system with the non-free Flash browser plugin. Works just fine for my needs. Enjoy. Show Sample Output


    18
    for i in ~/.adobe ~/.macromedia ; do ( rm $i/ -rf ; ln -s /dev/null $i ) ; done
    mhs · 2010-12-29 13:23:48 14
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Which processes are listening on a specific port (e.g. port 80)
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Print a file to a LPD server
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download 10 random wallpapers from google
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shorter typing with no need to use xargs.

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Get simple weather info from a zip code
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Fast tape rewind
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Show all machines on the network
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GRUB2: set Super Mario as startup tune
I'll let Slayer handle that. Raining Blood for your pleasure.

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