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Commands by b_t

Commands by b_t from sorted by
Terminal - Commands by b_t - 19 results
sort -M filename
2011-12-10 12:50:30
User: b_t
Functions: sort
Tags: sort
2
Up
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sort monthwise

sort command can sort month-wise (first three letters of each month).

See the sample output for clarification.

Sorting Stable ? NO. Take note if that matters to you.

Sample output suggests that sort performs unstable

sorting (see the relative order of two 'feb' entries).

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$ history -a #in one shell , and $ history -r #in another running shell
2011-11-05 01:19:30
User: b_t
Tags: history bash
10
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Instantly load bash history of one shell into another running shell

By default bash history of a shell is appended (appended on Ubuntu by default: Look for 'shopt -s histappend' in ~/.bashrc) to history file only after that shell exits.

Although after having written to the history file, other running shells do *not* inherit

that history - only newly launched shells do.

This pair of commands alleviate that.

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function whichpkg() { readlink -f "$(which $1)" | xargs --no-run-if-empty dpkg -S; }
2011-10-28 02:53:19
User: b_t
Functions: readlink xargs
Tags: xargs dpkg readlink
6
Up
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Find out which debian package a command (executable) belongs to on debian-based distros

This revision to my command (command #8851) was called for when it failed to find the parent

package of 'rlogin', which is really a deep symbolic link to /usr/bin/ssh.

This revision fixes this newfound issue, while ensuring fixes of other older issues work too.

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shopt -s histverify
2011-10-27 00:33:34
User: b_t
Tags: history bash
13
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Verify/edit bash history command before executing it

Bash history commands are those that begin with the character !

(eg. the most popular 'sudo !!' Explained here => http://www.commandlinefu.com/commands/view/13).

By default bash immediately executes the history command.

Setting this shell option will make bash first allow you to verify/edit an

history command before executing it.

To set this option permanently, put this command in ~/.profile or ~/.bashrc file.

To unset this option issue following command.

shopt -u histverify
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whichpkg () { dpkg -S $1 | egrep -w $(readlink -f "$(which $1)")$; }
2011-07-17 13:39:56
User: b_t
Functions: egrep readlink
Tags: dpkg readlink
1
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Find the package a command belongs to on debian-based distros

Advanced revision to the command 8776 . This revision follows symbolic links.

The quotation-marks surrounding $(which $1) allows for graceful handling of errors ( ie. readlink does not complain incase 'which' command generates (null) output)

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function summpkg { dpkg -s $(dpkg -S $1 | egrep -w $(which $1)$ | awk -F: '{print $1}') ; }
2011-07-05 23:06:37
User: b_t
Functions: awk egrep which
Tags: which dpkg
0
Up
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A command's package details

This version builds on my command 8776 (Find the package a command belongs to on debian-based distros). So if you use that command to find package name then you could alternatively use following for

package summary:

function summpkg { dpkg -s $(whichpkg $1 | awk -F: '{print $1}'); }
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function whichpkg { dpkg -S $1 | egrep -w $(which $1)$; }
2011-07-05 22:56:48
User: b_t
Functions: egrep which
Tags: dpkg
0
Up
Down
Find the package a command belongs to on debian-based distros

Similar to command 7822, but handles errors gracefully.

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curl -s http://example.com | grep -o -P "<a.*href.*>" | grep -o "http.*.pdf" | xargs -d"\n" -n1 wget -c
2011-06-09 14:42:46
User: b_t
Functions: grep wget xargs
Tags: xargs wget grep pdf html cur
0
Up
Down
Get all files of particular type (say, PDF) listed on some wegpage (say, example.com)

This example command fetches 'example.com' webpage and then fetches+saves all PDF files listed (linked to) on that webpage.

[*Note: of course there are no PDFs on example.com. This is just an example]

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make -d | egrep --color -i '(considering|older|newer|remake)'
2011-06-03 01:55:08
User: b_t
Functions: egrep make
Tags: make
1
Up
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Debug your makefile

Say your dependencies specified in your Makefile (or dates on your source files) is causing 'make' to

skip some source-files (that it should not) or on the other other end, if it is causing make to always build some source-files regardless of dates of target, then above command is handy to find out what 'make' thinks of your date v/s target date-wise or what dependencies are in make's view-point.

The egrep part removes the extra noise, that you might want to avoid.

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git push origin :featureless
2011-06-02 14:53:31
User: b_t
Tags: git
-1
Up
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Deleting a remote git branch (say, by name 'featureless')

This will delete the branch 'featureless' on the origin remote.

Do not forget to delete the branch locally using:

git branch -d featureless

'I got it here'-credit:

http://gitready.com/beginner/2009/02/02/push-and-delete-branches.html

I duplicated here incase you stumbled here first.

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ls | grep '^[A-Z0-9]*$'
2010-12-19 21:45:53
User: b_t
Functions: grep ls
Tags: upcase, uppercase, ls grep regex
0
Up
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List only those files that has all uppercase letters in their names (e.g. README)

Some source package have many 'README' kind of files, among many other regular files/directories. This command could be useful when one wants to list only 'README' kind of files among jungle of other files. (e.g. I came across this situation after downloading source for module-init-tools)

Warning: This command would miss a file like => README.1 (or one with spaces in-between)

Corrections welcome.

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kill -l
2010-11-17 23:48:51
User: b_t
Functions: kill
6
Up
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Signals list by NUMBER and NAME

This command seems to achieve the similar/same goal.

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history | awk '{print $2,$3}' | sed s/sudo// | awk '{print $1}' | awk 'BEGIN {FS="|"}{print $1}' | sort | uniq -c | sort -n | tail | sort -nr
2010-11-17 12:15:04
User: b_t
Functions: awk sed sort tail uniq
0
Up
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Ranking of the most frequently used commands

Your version works fine except for someone who's interested in commands 'sudo' was prefixed to

i.e. in your command, use of sudo appears as number of times sudo was used.

Slight variation in my command peeks into what commands sudo was used for and counts the command

(ignores 'sudo')

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lst=`dpkg -L iptables` ; for f in $lst; do if [ -x $f ] && [ ! -d $f ] ; then echo $f; fi; done;
2010-10-30 14:47:45
User: b_t
Functions: echo
Tags: dpkg package executable
1
Up
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List only executables installed by a debian package

I wanted to view only executables installed by a package. This seemed to work.

There's got to be easier way, please share.

Note:

(1) Replace iptables with the package name of your interest

(2) The command will trash any existing environment variable named 'lst'

(3) Instead if you are interested in viewing just .ko or .so files installed by this package, then

that would be easy:

$ dpkg -L iptables | grep "\.[sk]o$"

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wn wonder -over
2010-10-05 13:56:06
User: b_t
Tags: dictionary
2
Up
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commandline dictionary

Note:

1) Replace 'wonder' with any word you looking the meaning for in the above example

2) Need to install these packages:

wordnet & wordnet-base (latter should be automatically installed because of dependency)

3) Combined size of packages is about 30MB on my old ubuntu system (I find it worth it)

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gksudo gedit /etc/passwd &
2010-10-05 13:11:04
User: b_t
Tags: sudo GUI background
1
Up
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sudo for launching gui apps in background

Need package: gksu

Note:

Launching gui app in background that needs sudo, won't work great with our old

friendly style of launching:

sudo gedit /etc/passwd &

because this would put sudo in background !

Using gksudo as demonstrated, would popup a gui sudo window.

May be this is a common knowledge, but not knowing this

frustrated me during my newbie year.

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sudo -K
2010-10-05 12:44:26
User: b_t
Functions: sudo
Tags: Security sudo privacy
16
Up
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Make sudo forget password instantly

By default sudo 'remembers' password for a few minutes, so that you do not need to re-enter password for a series of sudo commands that might follow within a short time duration.

However, sometime you might want sudo to instantly 'forget' the password.

(Next sudo command will need you to reenter the password)

Credit: I first learned this while listening to one of the 'tuxradar' podcast.

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watch -n 900 "notify-send -t 10000 'Look away. Rest your eyes'"
2010-10-05 09:39:31
User: b_t
Functions: watch
Tags: notify-send watch reminder
0
Up
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Remind yourself every 15 minutes (repeated reminders)

Note:

1) -n option of watch accepts seconds

2) -t option of notify-send accepts milliseconds

3) All quotes stated in the given example are required if notification

message is more than a word.

4) I couldn't get this to run in background (use of & at the end fails). Any

suggestions/improvements welcome.

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file /bin/* | msort -j -l -n-1 -n2 2> /dev/null
2010-10-05 00:37:33
User: b_t
Functions: file
Tags: sort msort
4
Up
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Sort on multiple dis-contiguous keys/fields (can even specify key number/field from the end)

Notes:

1) -n-1 means sort key is the last field

2) -l is important if each separate record is on a new line (usually so for text files)

3) -j tells msort not to create log file (msort.log) in the working directory

4) may need to install msort package.

5) msort does lot more. Check man msort

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