Commands by mhs (29)


  • 2
    NSPR_LOG_MODULES=nsHostResolver:5 NSPR_LOG_FILE=/tmp/log.txt firefox
    mhs · 2015-09-30 01:56:36 0

  • 1
    dnstop -l 3 enp1s0f0
    mhs · 2015-09-30 01:55:11 0
  • 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 3
  • 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 1

  • 2
    lstopo -p -v --whole-system --whole-io output.svg
    mhs · 2015-01-27 15:16:54 1
  • 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 0
  • 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 0

  • 1
    xset b 50 1700 10
    mhs · 2015-01-27 14:38:58 0
  • 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 0
  • 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 0
  • 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 3
  • 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 2
  • 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 2
  • 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 7
  • 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 0
  • 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 3
  • `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 0
  • 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 0
  • `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 2
  • 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 1
  • 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 2

  • 6
    lshw -short
    mhs · 2011-06-28 23:32:30 3
  • 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`.


    12
    echo "${0%/*}"
    mhs · 2011-04-17 12:09:56 6
  • 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 0
  • 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 6
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Create the oauth token required for a Twitter stream feed
This is the THIRD in a set of five commands. See my other commands for the previous two. This step creates the oauth 1.0 token as explained in http://oauth.net/core/1.0/ The token is required for a Twitter filtered stream feed (and almost all Twitter API calls) This token is simply an encrypted version of your base string. The encryption key used is your hmac. The last part of the command scans the Base64 token string for '+', '/', and '=' characters and converts them to percentage-hex escape codes. (URI-escapeing). This is also a good example of where the $() syntax of Bash command substitution fails, while the backtick form ` works - the right parenthesis in the case statement causes a syntax error if you try to use the $() syntax here. See my previous two commands step1 and step2 to see how the base string variable $b and hmac variable $hmac are generated.

Get http headers for an url

List just the executable files (or directories) in current directory
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Set random background image in gnome
Changes your desktop background image in gnome. Update the directory to wherever you keep your wallpapers. I like to create a sub-directory in my Wallpaper folder called "cycle" that I use to define the wallpapers I wish to loop in cron. ex: $ gconftool-2 -t str -s /desktop/gnome/background/picture_filename "$(find ~/Wallpapers/cycle -type f | shuf -n1)"

Display network pc "name" and "workgroup"
Checks for PC samba name and workgroup. Works fine for Windows hosts and Linux/UNIX PCs running Samba.

Use Vim to convert text to HTML.
``vimhtml somefile.txt`` will open vim for the HTML convertion and close it immediately after its done, leaving you with somefile.html which you can later use in your website or whatever.

wrap long lines of a text
wraps text lines at the specified width (90 here). -s option is to force to wrap on blank characters -b count bytes instead of columns

Use the builtin ':' bash command to increment variables
I just found another use for the builtin ':' bash command. It increments counters for me in a loop if a certain condition is met... : [arguments] No effect; the command does nothing beyond expanding arguments and performing any specified redirections. A zero exit code is returned.

Benchmark SQL Query
Benchmark a SQL query against MySQL Server. The example runs the query 10 times, and you get the average runtime in the output. To ensure that the query does not get cached, use `RESET QUERY CACHE;` on top in the query file.


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