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 6
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 5
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 2
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 2
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 2

bash -x ./post_to_commandlinefu.sh

nottings · 2009-02-25 19:10:21 17

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 4
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 4
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 5
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 3
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 13
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 4
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 5

What's this?

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Get a BOFH excuse

Almost same output with fewer typing... OP had a great idea : BOFH !!!

Mount important virtual system directories under chroot'ed directory

The command is useful when, e.g., booting an existing system with a rescue or installation CD where you need to chroot into the hard-disk and be able to do stuff which accesses kernel info (e.g. when installing Ubuntu desktop with LVM2 you need to mount and chroot the hard disk from a shell window in order to install packages and run initramfs inside chroot). The command assumes that /mnt/xxx is where the chroot'ed environment's root file system on the hard disk is mounted.

Calculate days on which Friday the 13th occurs (inspired from the work of the user justsomeguy)

Friday is the 5th day of the week, monday is the 1st. Output may be affected by locale.

Scan your LAN for unauthorized IPs

populate the auth.hosts file with a list of IP addresses that are authorized to be in use and when you run this command it will return the addresses that are pingable and not in the authorized list. Can be combined with the "Command line Twitter" command to tweet unauthorized access.

Awesomeness Confirmation Bias

Restore user,group and mod of an entire website

I often use it at my work, on an ovh server with root ssh access and often have to change mod after having finished an operation. This command, replace the user, group and mod by the one required by apache to work.

convert .bin / .cue into .iso image

bchunk [-v] [-p] [-r] [-w] [-s]

List all symbolic links in current directory

For those who don't have the symlinks command, you can use readlink. This command is not straightforward because readlink is very picky. The backslash in front of 'ls' means not to use an alias (e.g. color escape codes from an aliased 'ls' could mess up readlink), and the -1 (one) means to print the entries separated by newlines. xargs -l (the letter L) means to process each input separated by newlines as separate commands.

Install pip with Proxy

Installs pip packages defining a proxy

Test network speed without wasting disk

The above command will send 4GB of data from one host to the next over the network, without consuming any unnecessary disk on either the client nor the host. This is a quick and dirty way to benchmark network speed without wasting any time or disk space. Of course, change the byte size and count as necessary. This command also doesn't rely on any extra 3rd party utilities, as dd, ssh, cat, /dev/zero and /dev/null are installed on all major Unix-like operating systems.

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