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Functions

Commands by mhs from sorted by
Terminal - Commands by mhs - 29 results
NSPR_LOG_MODULES=nsHostResolver:5 NSPR_LOG_FILE=/tmp/log.txt firefox
2015-09-30 01:56:36
User: mhs
Tags: firefox dns CLFUContest
2
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Monitor all DNS queries made by Firefox
Comments (9) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
dnstop -l 3 enp1s0f0
2015-09-30 01:55:11
User: mhs
Tags: dns CLFUContest dnstop
1
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Monitor all DNS queries seen by the local machine
Comments (9) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
i=in.swf; dump-gnash -1 -j 1280 -k 720 -D "${i%.*}"[email protected] -A "${i%.*}".wav "${i}"
2015-05-06 23:52:39
User: mhs
Tags: ffmpeg dump-gnash
0
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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
Comments (6) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
udevadm info -q all -n /dev/sdc | grep ID_PATH | cut -d'-' -f 2 | xargs -n 1 lspci -s
2015-01-27 15:34:02
User: mhs
Functions: cut grep info lspci xargs
Tags: lspci udevadm
1
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Find which fibre HBA a disk is connected to

Useful for big systems with lots of cards.

(Update: does not work with USB disks)

Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
lstopo -p -v --whole-system --whole-io output.svg
2015-01-27 15:16:54
User: mhs
Tags: lstopo
2
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Generate map of your hardware
Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
dmidecode --type 9 |egrep 'Bus Address|Designation'
2015-01-27 15:13:59
User: mhs
Functions: egrep
Tags: dmidecode
1
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Map the slot of an I/O card to its PCI bus address

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

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
aptitude --purge remove ~i^foo ~i^bar
2015-01-27 15:00:48
User: mhs
Tags: aptitude
1
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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.

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
xset b 50 1700 10
2015-01-27 14:38:58
User: mhs
Tags: beep xset
1
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Nice beep
Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
[ ! -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
2014-05-10 06:01:06
User: mhs
Functions: mkdir mv
Tags: performance ssd squashfs
4
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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

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
sdparm -s SCT=36000 --save /dev/sdb
2013-04-19 13:26:18
User: mhs
Tags: sdparm
2
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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.

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
prlimit --cpu=10 sort -u hugefile
2013-02-27 15:59:11
User: mhs
Functions: sort
Tags: cpu util-linux
4
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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
Comments (3) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
soffice --headless -convert-to odt:"writer8" somefile.docx
2012-12-27 15:08:38
User: mhs
Tags: convert libreoffice soffice
14
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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).

Comments (76) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
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
2012-12-26 13:21:18
User: mhs
Tags: screenshot adb android
8
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Android PNG screenshot

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

Comments (4) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
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
2012-12-26 11:35:23
User: mhs
Functions: tabs
Tags: contacts adb android sms sqlite3
2
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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
Comments (3) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
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'
2012-12-26 09:03:55
User: mhs
Functions: wget
Tags: wget sharepoint cntlm
1
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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

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
socat unix-connect:/tmp/socket stdio,echo=0,raw
2012-12-19 07:58:09
User: mhs
Tags: serial console socat vmware
1
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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).

Comments (4) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
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
2012-09-12 15:30:36
User: mhs
Functions: awk grep set
Tags: multipath parted
1
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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

Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
for i in /sys/block/sd* ; do wwn=`/lib/udev/scsi_id -g -s /block/${i##*/}` ; [ "$wwn" != "" ] && echo -e ${i##*/}'\t'$wwn ;done
2012-09-12 14:14:53
User: mhs
Functions: echo
Tags: sysfs WWN LUNs scsi_id
1
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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 | Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
blkid -c /dev/null
2012-09-12 13:34:41
User: mhs
Tags: partition uuid sysfs blkid util-linux
2
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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 | Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
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
2012-02-25 01:49:45
User: mhs
Functions: awk cp cut echo grep read sed tr
Tags: youtube flash flv exiftool tmpfs
8
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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.

Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
exec -a "/sbin/getty 38400 tty7" your_cmd -erase_all_files
2012-02-01 10:54:03
User: mhs
Functions: exec
Tags: exec ps process table
16
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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 | Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
lshw -short
2011-06-28 23:32:30
User: mhs
Tags: lshw ioscan
6
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Show 'Hardware path'-style tree of all devices in Linux
Show sample output | Comments (3) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
echo "${0%/*}"
2011-04-17 12:09:56
User: mhs
Functions: echo
Tags: Process Management parameter expansion special parameters
11
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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`.

Comments (6) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
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'
2011-02-08 09:37:05
User: mhs
Tags: mailutil IMAP
2
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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.

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for i in ~/.adobe ~/.macromedia ; do ( rm $i/ -rf ; ln -s /dev/null $i ) ; done
2010-12-29 13:23:48
User: mhs
Functions: ln rm
Tags: flash LSO cookies
18
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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 | Comments (8) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate