Posts Tagged ‘Shell’
Saturday, March 23rd, 2013
As a system administrator, sometimes is necessary to do basic plain text processing for various sysadmin tasks. One very common task I do to remove empty lines in file. There are plenty of ways to do it i.e. – with grep, sed, awk, bash, perl etc.
1. Deleting empty file lines with sed
The most standard way to do it is with sed, as sed was written to do in shell quick regexp. Here is how;
sed '/^\s*$/d' file_with_empty_lines.txt > output_no_empty_lines.txt
2. Deleting empty file lines with awk
It is less of writting with awk, but I always forget the syntax and thus I like more sed, anyways here is how with awk;
cat file_with_empty_lines.txt | awk 'NF' >
output_no_empty_lines.txt
3. Deleting empty lines with grep
Grep regular expression can be used. Here is grep cmd to cut off empty lines from file;
grep -v '^\s*$' file_with_empty_lines.txt >
output_no_empty_lines.txt
4. Delete empty files with vi / vim text editor
Open vi / vim text editor
$ vim
Press Esc+: and if empty lines doesn't have empty space characters use command
g/^$/d
Whether, empty lines contain " " – space characters (which are not visible in most text editors), use vi cmd:
g/^ $/d
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Tags: empty space, grep, Linux, Perl, regexp, regular expression, Shell, space characters, syntax, system administrator, text editors, vim text editor, writting
Posted in Linux, Programming, System Administration, Various | No Comments »
Thursday, March 14th, 2013
I had to configure a newly purchased dedicated server from UK2. New servers cames shipped with some random assigned node hostname like server42803. This is pretty annoying, and has to be changed especially if your company has a naming server policy in some format like; company-s1#, company-s2#, company-sN#.
Changing hostname via hosts definition file /etc/hosts to assign the IP address of the host to the hostname is not enough for changing the hostname shown in shell via SSH user login.
To display full hostname on Debian and Ubuntu, had to type:
server42803:~# hostname
server42803.uk2net.com
To change permanently server host to lets say company-s5;
server42803:~# cat /etc/hostname | \
sed -e 's#server42803.uk2net.com#company-s5#' > /etc/hostname
To change for current logged in SSH session:
server42803:~# hostname company-s5
company-s5:~#
Finally because already old hostname is red by sshd, you have to also restart sshd for new hostname to be visible on user ssh:
company-s5:~# /etc/init.d/ssh restart
...
As well as run script:
company-s5:~# /etc/init.d/hostname.sh
Mission change host accomplished, Enjoy 
Tags: hostname, hosts, ip address, Linux, node, server host, server policy, servers, session 3a, Shell, sshd, type 3a, ubuntu linux
Posted in Everyday Life, Linux, System Administration, Various | No Comments »
Thursday, January 17th, 2013
For web development purposes it is necessery to copy MySQL SQL database schema structure without copying the filled in data. A typical case where a replicate of SQL server structure is needed to be installed on another server is on whether a client is bying a new website and it is planned his website Database Design is similar or same like another already working productive website.
Thanksfully, one doesn't have to script in perl or bash cause mysqldump dump tool has already integrated option for that (–no-data).
Here what mysqldump man page says of –no-data;
–no-data, -d
Do not write any table row information (that is, do not dump table contents). This is useful if you want to dump only the
CREATE TABLE statement for the table (for example, to create an empty copy of the table by loading the dump file).
1. Moving SQL data scheme for all databases in MySQL Server
On host with SQL containing productive data, to dump only the structure of databases / tables and table type, fields rows etc.:
host1# mysqldump -d -h localhost -u root -p'your_password' >sql-all-dbs-tables-empty-structure.sql
Then on the secondary MySQL server, where empty SQL structure (without any filled in info) is needed run:
host2# mysql -u root -p'your_password' < sql-all-dbs-tables-empty-structure.sql
2. Moving SQL data structure for only concrete database
On Linux host1 shell issue;
host1# mysqldump -d -h localhost -u root -p'your_password' database_name>sql-database-empty-structure.sql
On host2 server type;
host2# mysql -u root -p'your_password' < sql-database-empty-structure.sql
3. Moving SQL data structure for few databases
Lets say you have a user (new_user), who has privileges over a number of databases and you want to dump a dump copy of those empty databases;
Same like with one table, just include names of all databases scheme to dump;
host1# mysqldump -d -h localhost -u new_user -p'your_password' database_name atabase_name2 database_whatever >sql-only-some-databases-structure.sql
Then to import on host2 again;
host2# mysql -u new_user -p'your_password' < sql-only-some-databases-structure.sql
4. Dumping and copying only database names from one MySQL to another
Though the case might be rary you might need to dump and copy only list of all databases existing without recreating table database sub-structure. This is doable like so:
On SQL node host1 run;
host1# for i in $(echo "show databases;" | mysql -u root -p|grep -v -E 'Database$' |grep -v information_schema); do echo $i >> structure.txt; done
host2# for i in $(cat structure.txt); do echo "create database $i;" | mysql -u root -p; done
Though I've tested all this and it is safe to use, if you're re-creating SQL database / tables structure make sure you have a working copy of data from SQL.
Well that's it hope this little article helps someone
Tags: data structure, database design, database schema, development purposes, dump tool, host1, Linux, localhost, productive website, schema, Shell, sql database, table contents, table structure, typical case
Posted in Everyday Life, Linux, MySQL, Web and CMS | No Comments »
Friday, July 27th, 2012
I’ve used K3B just recently to RIP an Audio CD with music to MP3. K3b has done a great job ripping the tracks, the only problem was By default k3b RIPs songs in OGG Vorbis (.ogg) and not mp3. I personally prefer OGG Vorbis as it is a free freedom respecting audio format, however the problem was the .ogg-s cannot be read on many of the audio players and it could be a problem reading the RIPped oggs on Windows. I’ve done the RIP not for myself but for a Belarusian gfriend of mine and she is completely computer illiterate and if I pass her the songs in .OGG, there is no chance she succed in listening the oggs. I’ve seen later k3b has an option to choose to convert directly to MP3 Using linux mp3 lame library this however is time consuming and I have to wait another 10 minutes or so for the songs to be ripped to shorten the time I decided to directly convert the existing .ogg files to .mp3 on my (Debian Linux). There are probably many ways to convert .ogg to mp3 on linux and likely many GUI frontends (like SoundConverter) to use in graphic env.
I however am a console freak so I preferred doing it from terminal. I’ve done quick research on the net and figured out the good old ffmpeg is capable of converting .oggs to .mp3s. To convert all mp3s just ripped in the separate directory I had to run ffmpeg in a tiny bash loop.
A short bash shell script 1 liner combined with ffmpeg does it, e.g.;
for f in *.ogg; do ffmpeg -i "$f" "`basename "$f" .ogg`.mp3"; done.....
The loop example is in bash so in order to make the code work on FreeBSD it is necessery it is run in a bash shell and not in BSDs so common csh or tcsh.
Well, that’s all oggs are in mp3; Hip-hip Hooray 
Tags: audio cd, Auto, basename, bash shell script, BSDs, chance, code, consuming, csh, debian linux, Draft, ffmpeg, format, freak, freebsd, freedom, frontends, GNU, gnu linux, job, k3b, Linux, necessery, Ogg, ogg files, oggs, option, RIPs, script, Shell, soundconverter, terminal, time, time consuming, vorbis ogg, work
Posted in Everyday Life, FreeBSD, Linux and FreeBSD Desktop, Linux Audio & Video | 1 Comment »
Friday, July 20th, 2012
I'm running a two servers for a couple of home hosted websites. One of the servers is serving as Apache host1 and has configured MySQL running on it and the second is used just for database host2 – (has another MySQL configured on it).
The MySQL servers are not configured to run as a MySQL MASTER and MySQL SLAVE (no mysql replication), however periodically (daily), I have a tiny shell script that is actualizing the data from the active SQL host2 server to host1.
Sometimes due to electricity problems or CPU overheats the active MySQL host at host2 gets stoned and stops working causing the 2 WordPress based websites and One joomla site inaccessible.
Until I manually get to the machine and restart host2 the 3 sites are down from the net and as you can imagine this has a very negative impact on the existing website indexing (PageRank) in Google.
When I'm at home, this is not a problem as I have physical access to the servers and if somethings gets messy I fix it quickly. The problem comes, whether I'm travelling or in another city far from home and there is no-one at home to give the hanged host hard reboot ….
Lately the problems with hang-ups of host2 happaned 3 times or so for 2 weeks, as a result the websites were inaccessible for hours and since there is nobody to reboot the server for hours; the websites keep hanging until the DB host is restarted ;;;;
To work-around this I came with the idea to write a tiny shell script to check if host2 is ping-able in order to assure the Database host is not down and then if script determines host2 (mysql) host is down it changes wp-config.php (set to use host2) to a wp-config.php (which I have beforehand configured to use) host1.
Using the script is a temporary solution, since I have to actually find the real hang-up causing troubles, but at least it saves me long downtimes. Here is a download link to the script I called change_blog_db.sh .
I've configured the script to be run on the Apache node (host1) via a crontab calling the script every 10 minutes, here is the crontab:
*/10 * * * * /usr/sbin/change_blog_db.sh > /dev/null 2>&1
The script is written in a way so if it determins host2 is reachable a copy of wp-config.php and Joomla's configuration.php tuned to use host2 is copied over the file config originals. In order to use the script one has to configured the head variables script section, e.g.:
host_to_ping='192.168.0.2';
blog_dir='/var/www/blog';
blog_dir2='/var/www/blog1';blog_dir3='/var/www/joomla';
notify_mail='hipo@pc-freak.net';
wp_config_orig='wp-config.php';
wp_config_localhost='wp-config-localhost.php';
wp_config_other_host='wp-config-192.168.0.2.php';
joomla_config_orig='configuration.php';
joomla_config_other_host='configuration-192.168.0.2.php';
You will have to manually prepare;;;
wp-config-localhost.php, wp-config-192.168.0.2.php ,configuration-192.168.0.2.php, wp-config-localhost.php to be existing files configured to with proper host1 and host2 IP addresses.
Hope the script will be useful to others, experiencing database downtimes with WordPress or Joomla installs.
Tags: apache, change, city, config, copy, cpu overheats, database host, download, electricity, electricity problems, file, google, hang ups, HEAD, host1, impact, indexing, Master, mysql replication, mysql server, mysql servers, negative impact, nobody, one at home, orig, pagerank, php, ping, replication, second, Shell, shell script, SQL, temporary solution, tiny shell, ups, website indexing, Wordpress
Posted in Joomla, MySQL, Various, Web and CMS, Wordpress | 2 Comments »
Wednesday, July 18th, 2012
At security critical hosts running Apache + PHP based sites it is recommended functions like:
system();
exec();shell_exec();.....
to be disabled. The reason is to mainly harden against script kiddies who might exploit your site/s and upload some shitty SK tool like PHP WebShell, PHP Shell and the probably thousands of “hacker” variations that exist nowdays.
In latest Debian stable Squeeze, suhosin – advanced protection module for php5 is being installed and enabled in Apache (by default).
Simply disabling a number of functions using suhosin, could prevent multiple of future headaches and hours of pondering on who 0wn3d your server ….
Disabling the basic PHP system(); and other similar functions which allows shell spawn is not always possible, since some websites or CMS platforms depends on them for proper runnig, anyways whether it is possible disabling ‘em is a must.
There are two ways to disable system(); functions; One is through using /etc/php5/apache2/conf.d/suhosin.ini and 2nd by adding a list of functions that has to be disabled directly in Website Virtualhost file or in apache2.conf (/etc/apache2/apache2.conf;
For people hosting multiple virtualhost websites on the same server using the custom domain Virtualhost method is probably better, since on a global scale the functions could be enabled if some of the websites hosted on the server requires exec(); to work OK. In any case using /etc/php5/apache2/conf.d/suhosin.ini to disable system(); functions in PHP is less messy …
1. Disabling PHP system(); fuctions through /etc/apache2/apache2.conf and custom site Vhosts
Place somewhere (I prefer near the end of config);;;
php_admin_flag safe_mode on
php_admin_value disable_functions "system, exec, shell_exec, passthru , ini_alter, dl, pfsockopen, openlog, syslog, readlink, symlink, link, leak, fsockopen, popen, escapeshellcmd, apache_child_terminate apache_get_modules, apache_get_version, apache_getenv, apache_note,apache_setenv,virtual"
Disabling it for custom virtualhost is done by simply adding above Apache directvies (before the closing tag in /etc/apache2/sites-enabled/custom-vhost.com
2. Disabling PHP system();, exec(); shell spawn with suhosin.ini
In /etc/php5/apache2/conf.d/suhosin.ini add;;
suhosin.executor.func.blacklist =system, exec, shell_exec, passthru, ini_alter, dl,
pfsockopen, openlog, syslog, readlink, symlink, link, leak, fsockopen, popen,
escapeshellcmd, apache_child_terminate apache_get_modules, apache_get_version,
apache_getenv, apache_note,apache_setenv,virtual
To do it directly via shell issue;;;
server: conf.d/# cd /etc/php5/apache2/conf.d/
server: conf.d# echo 'suhosin.executor.func.blacklist =system, exec, shell_exec, passthru, ini_alter, dl,' >> suhosin.ini
server: conf.d# echo 'pfsockopen, openlog, syslog, readlink, symlink, link, leak, fsockopen, popen,' >> suhosin.ini
server: conf.d# echo escapeshellcmd, apache_child_terminate apache_get_modules, apache_get_version,' >> suhosin.ini
server: conf.d# echo 'apache_getenv, apache_note,apache_setenv,virtual' >> suhosin.ini
Then to re-load the memory loaded Apache libphp library an Apache restart is necessary;
server: conf.d# /etc/init.d/apache2 restart
Restarting web server: apache2 ... waiting .
server: conf.d#
Tadam, this should be quite a good security against annoying automated script attacks. Cheers
Tags: apache security, apache2, Auto, custom, custom domain, debian gnu, Draft, escapeshellcmd, exec, func, global scale, GNU, gnu linux, harden, headaches, ini, Linux, number, passthru, php admin, php5, popen, protection, reason, runnig, safe mode, script, script kiddies, Shell, squeeze, suhosin, symlink, syslog, system, system functions, tool, two ways, VhostsPlace, Virtualhost, WebShell
Posted in Computer Security, System Administration, Web and CMS | 2 Comments »
Wednesday, July 4th, 2012
I've been given a HUAWEI Mobile Broadband E173 USB 3g model. The USB modem contains a flash USB Storage segment storing a little install program dedicated to make the modem work fine on Microsoft Windows XP / Vista / 7 and probably other M$ OSes. I'm a long time DebianGNU / Linux user and as a free software enthusiast I ofcourse wanted to be able to use Vivacom's 3G USB Modem on my Linux powered notebook.
Thanksfully as I've red on Vivacom's website the modem supports Linux OS
For those unaware in Bulgaria there are currently 3 major GSM network providers providing 3G internet this are;;;
- VIVACOM – The ex Government ran national company BTC (Bulgarian Telecommunication Company)
- M-Tel – The first GSM network provider that entered Bulgaria around year 1995
- GLOBUL – The 3rd and last GSM mobile and net provider entered last and not so much used by Bulgarians today
Until today I had no experience in running any 3G modems on Linux, neither I had used the 3 networks 3G internet to determine which one is best, however I've been given for temporal use a VIVACOM 3G internet modem today so I proceeded to try installing it on my Debian host.
My Linux system is a bit strangely configured as I use wicd network connection manager -( wicd-gtk ) to manage wireless and LAN connections instead of the standard installed GNOME network manager – available through package ( network-manager-gnome ).
The reason I use wicd is not that it is so much better than GNOME network manger but rather for historical reasons because few years past I had impression it works better in connecting me to wireless networks. Another reason why I choosed wicd back then was the nice looking stats …
I tried plugging in the Vivacom USB 3G modem stick and checked in wicd to see if I can see a possibility to connect to the mobile opeartor 3G network but unfortunately nothing appeared.
Though the 3G adsl modem was unavailable straing in wicd, checking about it in the list of attached USB devices I could see it detected, e.g.:
noah:~# lsusb |grep -i huawei
Bus 001 Device 007: ID 12d1:1c05 Huawei Technologies Co., Ltd.
This was at least a good sign pointing me to the thoughts that the modem is probably gonna work.
I did a quick Google search to see if other people succeded running the device on a Linux host and came across a few blog posts in Bulgarian explaining a "success story" on Ubuntu Linux through using a tweakened shell script – sakis3g. For more on how the script works and script download check out Sakis3g
Here is a quote from sakis3g's website describing the script:
It automagically setups your USB or Bluetooth™ modem, and may even detect operator settings.
You should try it when anything else fails!
Sakis3g has different versions designed for for plenty of spacific hware architectures i.e. for (i386, amd64, armv4t, armv5t).
There is also a version of the script which by the way contains a combination of bash shell scripting instruction and some binary exec data.
To run sakis3g on my laptop I did:
1. Download sakis3g
My notebook architecture is 64 bit so I download and used the amd64 version of the script;;;
hipo@noah:~$ mkdir sakis3g
hipo@noah:~$ cd sakis3g
hipo@noah:~/sakis3g$ wget http://www.sakis3g.org/versions/latest/amd64/sakis3g.gz
I've made also a mirror of sakis3g i386, 64 bit and all architecture the mirrors just in case it disappears in future. The mirror versions of sakis3g are here:
a. sakis3g i386 b. sakis3g amd64 c. sakis3g all architectures source
2. Unarchive and make it executable
After downloading it as it is in gzip I had to do the usual de-gzipping and making the file executable;;;
hipo@noah:~/sakis3g$ /bin/gzip -d sakis3g.gz
hipo@noah:~/sakis3g$ chmod +x sakis3g
The script is then ready to run by either clicking twice on it or (as I prefer for debugging reasons to run it in terminal):
hipo@noah:~$ ./sakis3g
Something that I have wondered a bit was the dialog where I had to fill in some data of some variable APN abbreviation for – (Access Point Name)
The APN host for VIVACOM mobile internet is;;;
APN: internet.vivacom.bg
I've used the Windows configuration progrma to gather also the following data that I thought might be important for configuring the 3G adsl modem on the Linux host;;;
Auth: *99#
User: VIVACOM
pass: VIVACOM
Here are all the configuration screenshots I've taken from sakis3g and all the data that I filled in.
Next the following tiny window appeared on screen:
Well that's all folks, now sakis3g succesfully connected to the I_net via an (PPP) VPN connection tunnel here is data from ifconfig command showing the succesful 3G connection to VIVACOM;;;
noah:~# /sbin/ifconfig ppp0
ppp0 Link encap:Point-to-Point Protocol
inet addr:10.58.146.232 P-t-P:10.64.64.64 Mask:255.255.255.255
UP POINTOPOINT RUNNING NOARP MULTICAST MTU:1500 Metric:1
RX packets:2066 errors:1 dropped:0 overruns:0 frame:0
TX packets:1609 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:3
RX bytes:2232058 (2.1 MiB) TX bytes:341693 (333.6 KiB)
The internet via the 3G connection is not blazing fast but good enough to check your mail or read some webpages. VIVACOM currently has different (traffic limited packages) for their 3G internet, I'm not sure which package exactly is the 3G USB stick modem but probably the "quick" internet connection that is now would slow down once the traffic limit is reached …
Hope this post helps someone to configure 3G internet on VIVACOM in Debian and Ubuntu Linux. Though I've tested sakis3g on Debian it should work with no hassles on any other GNU Linux distribution that has bash installed.
Tags: adsl modem, architecture, Auto, bulgarians, configure, connection, DebianGNU, download, Draft, Flash, flash usb, free software enthusiast, Gnome, GSM, gsm network, gzip, host, internet modem, lan connections, linux system, m tel, manager, microsoft windows, Mobile, modem work, modems, nbsp, network provider, network providers, Point, quot, reason, segment, Shell, software, telecommunication company, time, Ubuntu, usb internet, usb modem, wicd, wireless networks, work
Posted in Linux, Linux and FreeBSD Desktop, Various | 2 Comments »
Monday, June 11th, 2012
After writting in previous article on how talk be used to handle interactive chat console sessions on FreeBSD, I thought of dropping a few lines on how same is done on Debian, so here is how:
1.; Install talk and talkd
noah:/home/hipo# apt-get --yes install talk talkd
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following NEW packages will be installed:
talk talkd
0 upgraded, 2 newly installed, 0 to remove and 93 not upgraded.
Need to get 19.0 kB/42.3 kB of archives.
After this operation, 201 kB of additional disk space will be used.
Get:1 http://ftp.nl.debian.org/debian/ stable/main talkd amd64 0.17-14 [19.0 kB]
Fetched 19.0 kB in 0s (67.1 kB/s)
Selecting previously deselected package talk.
(Reading database ... 90%
Unpacking talk (from .../talk_0.17-14_amd64.deb) ...
Selecting previously deselected package talkd.
Unpacking talkd (from .../talkd_0.17-14_amd64.deb) ...
Processing triggers for man-db ...
Setting up talk (0.17-14) ...
update-alternatives: using /usr/bin/netkit-ntalk to provide /usr/bin/talk (talk) in auto mode.
Setting up talkd (0.17-14) ...
2.;; Check and make sure talk and ntalkd lines are present in /etc/inetd.conf
noah:/home/hipo# grep -i talk /etc/inetd.conf
#:BSD: Shell, login, exec and talk are BSD protocols.
talk dgram udp wait nobody.tty /usr/sbin/in.talkd in.talkd
ntalk dgram udp wait nobody.tty /usr/sbin/in.ntalkd in.ntalkd
Now you probably wonder why are there two lines in /etc/inetd.conf for ))
in.talkd and in.ntald
in.talkd daemon's aim is to deliver talk sessions between logged in users on one Linux host with few logged in users willing to talk to each other locally;;
Wheter in.ntalkd is designed to serve interactive user talks between the host where in.ntalkd is installed and remote systems ruwhich have the talk client program installed. Of course in order for remote talks to work properly the firewall (if such has to be modified to allow in.ntalkd chats. I've never used in.ntalkd and on most machines having in.ntald hanging around from inetd, could be a potential security hole so, for people not planning to initiate remote TALKs between Unix / Linux / BSD hosts on a network it is a good practice the ntalkd line seen above in inetd.conf to be commented out ::;
noah:/home/hipo# grep -i talk /etc/inetd.conf
#:BSD: Shell, login, exec and talk are BSD protocols.
talk dgram udp wait nobody.tty /usr/sbin/in.talkd in.talkd
#ntalk dgram udp wait nobody.tty /usr/sbin/in.ntalkd in.ntalkd
3.;;; Restart openbsd-inetd init script and talk is ready to use
noah:~# /etc/init.d/openbsd-inetd restart
* Restarting internet superserver inetd
Onwards to use talk between two users the syntax is same like on other BSD, as a matter of fact TALK – console / terminal interactive chat originally was developed for the 4.2BSD UNIX release ;; the Linux code is a port of this BSD talk and not rewrite from scratch.
Using talk between two logged in users on pts/1 (lets say user test) and tty1 (user logged as root) is done with:
noah:~$ tty
noah:~$ talk root@localhost tty1
/dev/pts/1
On tty1 the user has to have enabled Talk sessions request, by default this behaviour in Debian and probably other Debian based Linuxes (Ubuntu) for instance is configured to have talks disabled, i,e ,,,
root@noah:~# mesg
is n
Enabling it on root console is done with:
root@noah:~# mesg y
Once enabled the root will be able to see the TALK service requests on tty1 otherwise, the user gets nothing. With enabled messaging the root user will get on his tty:
Message from TalkDaemon@his_machine...
talk: connection requested by your_name@your_machine.
talk: respond with: talk your_name@your_machine
So on the root console to reply back to talk chat request:
noah:~$ talk hipo@localhost
Tags: aim, Auto, auto mode, building, confnoah, daemon, deb, debian gnu, dependency, dependency tree, dgram, Disk, disk space, DoneBuilding, Draft, exec, Fetched, freebsd, gnu linux, information, Install, interactive user, localhost, login, mesg, noah, nobody, ntalk, ntalkd, operation, package, protocols, reading database, reading package, request, root, sbin, sessions, Shell, shell login, state information, tree, wait, work, writting
Posted in Linux | No Comments »
Tuesday, May 8th, 2012
I believe, the quickest way to take notes on Linux and BSD and later view the notes is to use the command line.
A very easy simple way to keep record of various short notes is just to use a simple text editor like (vim) and store each note in a separate file in lets say ~/notes/ directory.
Actually, I'm using this way to take notes and store sensitive info for various important information I need for further reference, since 5 years or so..
Opening a new text editor for each note and then doing cd ~/notes/; ls |grep -i 'string' is a bit time consuming.
Fortunately there is a quick two shell functions hack that shortens time for note taking. The following two bash functions has to be added in ~/.bashrc:
n() {
vim ~/notes/"$*".txt
}
nls() {
ls -c ~/notes/ | grep "$1"
}
Copy / Paste this two functions in the beginning or the end of ~/.bashrc in order to use them.
Also if ~/notes directory is not existing, yet create it:
hipo@noah:~$ mkdir notes
To make the two new input functions active across opened bash shells on console or terminal either re-login or reread the .bashrc by "sourcing it", e.g.
hipo@noah:~$ source ~/.bashrc
Afterwards, note taking becomes a piece of cake to store a new note with login credentials (user/password) for a new registration to a random named website, type something like:
hipo@noah:~$ n my_website_name-user-pass
This will open for editting ~/.notes/my_website_name-user-pass.txt, type the new desired note content and do save and exit from vim (press esc and type 
!.
Then to get a quick list of all previously stored notes use:
hipo@noah:~$ nls website
my_website_name-user-pass.txt
If you already have a directory containing subdirectories with various taken notes (like me), you will need to use an improved version nls written by Jason Ryan, the nls improved is like this:
nls () { tree -CR --noreport ~/notes | awk '{
if ((NR >) gsub(/.txt/,"")); if
(NF==1) print $1; else if (NF==2)
print $2; else if (NF==3)
printf " %s\n", $3}';
}
This two functions, were not my creation but was suggested in Linux Magazine issue 135 article entitled Command-line task managers and note-taking tools written by Dmitri Popov.
Hope this two functions, will be helpful to console geeks out there.
Tags: Auto, BSD, cake, consuming, copy paste, cr, Draft, file, freebsd, gnu linux, hack, important information, info, information, input functions, jason ryan, Linux, login, login credentials, mkdir, need, nls, noah, opening, password, piece, piece of cake, sensitive info, Shell, shell functions, shells, something, subdirectories, terminal, text, time, txtIf, type, vim, websitemy
Posted in System Administration | 2 Comments »
Saturday, April 28th, 2012
If there is necessity to look for a string in all hidden files with all sub-level subdirectories (be aware this will be time consuming and CPU stressing) use:
hipo@noah:~$ grep -rli 'PATH' .*
./.gftp/gftprc
./.gftp/cache/cache.OOqZVP
….
Sometimes its necessery to only grep for variables within the first-level directories (lets say you would like to grep a 'PATH' variable set, string within the $HOME directory, the command is:
hipo@noah:~$ grep PATH .[!.]*
.profile:PATH=/bin:/usr/bin/:${PATH}
.profile:export PATH
.profile:# set PATH so it includes user's private bin if it exists
.profile: PATH="$HOME/bin:$PATH"
.profile.language-env-bak:# set PATH so it includes user's private bin if it exists
.profile.language-env-bak: PATH="$HOME/bin:$PATH"
.viminfo:?/PATH.xcyrillic: XNLSPATH=/usr/X11R6/lib/X11/nls
.xcyrillic: export XNLSPATH
The regular expression .[!.]*, means exclude any file or directory name starting with '..', e.g. match only .* files
Note that to use the grep PATH .[!.]* on FreeBSD you will have to use this regular expression in bash shell, the default BSD csh or tsch shells will not recognize the regular expression, e.g.:
grep PATH '.[!.]*'
grep: .[!.]*: No such file or directory
Hence on BSD, if you need to look up for a string within the home directory, hidden files: .profile .bashrc .bash_profile .cshrc run it under bash shell:
freebsd# /usr/local/bin/bash
[root@freebsd:/home/hipo]# grep PATH .[!.]*
.bash_profile:# set PATH so it includes user's private bin if it exists
.bash_profile:# PATH=~/bin:"${PATH}"
.bash_profile:# do the same with …
Another easier to remember, alternative grep cmd is:
hipo@noah:~$ grep PATH .*
.profile:PATH=/bin:/usr/bin/:${PATH}
.profile:export PATH
.profile:# set PATH so it includes user's private bin if it exists
.profile: PATH="$HOME/bin:$PATH"
….
Note that grep 'string' .* is a bit different in meaning, as it will not prevent grep to match filenames with names ..filename1, ..filename2 etc.
Though grep 'string' .* will work note that it will sometimes output some unwanted matches if filenames with double dot in the beginning of file name are there …
That's all folks
Tags: Auto, bash shell, bit, BSD, cache cache, cmd, consuming, csh, cshrc, directory name, Draft, export path, expression, file, freebsd, gftp, grep, hipo, home directory, level directories, Linux, MANPATHAnother, nbsp, necessery, noah, Path, path profile, private bin, profile path, quot, regular expression, rli, root, set path, Shell, shrc, text, text strings, time, time consuming, tsch, value, XNLSPATH, XNLSPATHThe, zcompdump
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