Commands by nottings

Commands by nottings (13)

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generate a randome 10 character password
This is sample output - yours may be different.
7

tr -dc A-Za-z0-9_ < /dev/urandom | head -c 10 | xargs

nottings · 2012-10-17 14:04:14 10
stop man page content from disappearing on exit

stop man page content from disappearing on exit echo "export LESS='FiX'" >> ~/.bashrc man bash 'q'uit out of man page content will stay on screen Show Sample Output
This is sample output - yours may be different.
```
man bash
'q'uit out of man page
content will stay on screen
```
7

echo "export LESS='FiX'" >> ~/.bashrc

nottings · 2010-11-08 21:58:25 8
Show exit status of all portions of a piped command eg. ls |this_doesn't_exist |wc
This is sample output - yours may be different.
5

echo ${PIPESTATUS[@]}

nottings · 2010-11-01 21:46:58 5
direct a single stream of input (ls) to multiple readers (grep & wc) without using temporary files
This is sample output - yours may be different.
8

ls |tee >(grep xxx |wc >xxx.count) >(grep yyy |wc >yyy.count) |grep zzz |wc >zzz.count

nottings · 2010-10-25 17:49:14 4
display date of last time a process was started in `date` format

STARTED Mon Oct 18 04:02:01 2010 Show Sample Output
This is sample output - yours may be different.
```
STARTED
Mon Oct 18 04:02:01 2010
```
5

ps -o lstart <pid>

nottings · 2010-10-18 17:09:02 5

bash -x ./post_to_commandlinefu.sh

nottings · 2009-02-25 19:10:21 54

skip broken piece of a loop but not exit the loop entirely

useful for loops like for i in $(cat list_of_servers); do ssh -q $i hostname; done if there is an unreachable server, you can just press ctrl + \ to skip that server and continue on with the loop
This is sample output - yours may be different.
7

ctrl + \

nottings · 2009-02-25 18:52:57 8
connect to X login screen via vnc

the $15 may change for you depending on your distro, etc...
This is sample output - yours may be different.
4

x11vnc -display :0 -auth $(ps -ef|awk '/xauth/ {print $15}'|head -1) -forever -bg &

nottings · 2009-02-19 18:55:54 5
read a file line by line and perform some operation on each line

see sample output Show Sample Output
This is sample output - yours may be different.
```
snottin@drifter /tmp $ cat > somefile.txt
line 1
line 2
line 3
snottin@drifter /tmp $ while read line; do echo "$(date),$(hostname),$line"; done < somefile.txt
Thu Feb 19 12:47:57 CST 2009,drifter,line 1
Thu Feb 19 12:47:57 CST 2009,drifter,line 2
Thu Feb 19 12:47:57 CST 2009,drifter,line 3
```
2

while read line; do echo "$(date),$(hostname),$line"; done < somefile.txt

nottings · 2009-02-19 18:48:12 7
use vi key bindings at the command line
This is sample output - yours may be different.
5

set -o vi

nottings · 2009-02-19 18:40:44 5
display contents of a file w/o any comments or blank lines
This is sample output - yours may be different.
4

egrep '^[^#]' some_file

nottings · 2009-02-19 17:35:52 15
open a seperate konsole tab and ssh to each of N servers (konsole 4.2+)

creates a new tab for each of N servers in listofservers.txt and ssh's to said servers then, try the "send to all sessions" feature of konsole to do the same work on all servers at the same time. BIG time saver, but be careful!
This is sample output - yours may be different.
4

for i in $(cat listofservers.txt); do konsole --new-tab -e ssh $i; done

nottings · 2009-02-19 16:32:36 8
Convert file type to unix utf-8

converts encoding of a file to unix utf-8 useful for data files that contain what would be usable ascii text but are encoded as mpeg or some other encoding that prevents you from doing common manipulations like 'sed' Show Sample Output
This is sample output - yours may be different.
```
[root@gaslight WAP_EMI_scans]# file datafile1.csv
datafile1.csv: MPEG ADTS, layer I, v1, 160 kBits, 32 kHz, Stereo
[root@gaslight WAP_EMI_scans]# ex datafile1.csv "+set ff=unix fileencoding=utf-8" "+x"
[root@gaslight WAP_EMI_scans]# file datafile1.csv
datafile1.csv: Unicode text, UTF-8
```
5

ex some_file "+set ff=unix fileencoding=utf-8" "+x"

nottings · 2009-02-19 16:23:21 7

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Calculate the distance between two geographic coordinates points (latitude longitude)

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The scene in the Shining (Stanley Kubrick)

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Get AWS temporary credentials ready to export based on a MFA virtual appliance

You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

List the biggest accessible files/dirs in current directory, sorted

Recursive Ownership Change

Changing files ownership in a directory recursivley from a user to another

Finding the number of cpu's

Show most common words in filenames

I'm sure there's a more elegant sed version for the tr + grep section.

sends your internal IP by email

This is useful if you have need to do port forwarding and your router doesn't assign static IPs, you can add it to a script in a cron job that checks if you IP as recently changed or with a trigger script. This was tested on Mac OSX.

Open (in vim) all modified files in a git repository

The option --porcelain makes the output of git easier to parse. This one-liner may not work if there is a space in the modified file name.

Save your terminal commands in bash history in real time

Use this command if you want your terminal commands be saved in your history file in real time instead of waiting until the terminal is closed

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