$ curl ifconfig.me $ curl icanhazip.com $ curl ident.me $ curl ipecho.net/plain $ curl whatismyip.akamai.com $ curl tnx.nl/ip $ curl myip.dnsomatic.com $ curl ip.appspot.com $ curl -s checkip.dyndns.org | sed 's/.*IP Address: \([0-9\.]*\).*/\1/g'
Dış IP’yi öğrenmek
Temmuz 30, 2013 § Yorum yok § Kalıcı bağlantı
History’i Silmek
Temmuz 30, 2013 § Yorum yok § Kalıcı bağlantı
Current Session historisini silmek
unset HISTFILE && exit
veya
kill -9 $$
Bütün History’i silmek
history -c && exit
HISTSIZE=0 && exit
rm -f $HISTFILE && unset HISTFILE && exit
İsminin Başında “-” Olan Dosyalarla Çalışmak
Temmuz 30, 2013 § Yorum yok § Kalıcı bağlantı
Aşağıdaki komut çalışmayacaktır. Zira -file dosyası bash tarafından lessin parametresi olarak algılanır.
less -file
Bunu aşmak için
less ./-file touch ./-test echo "test content to file" > ./-test cat ./-test rm ./-test
Cat İle Görünmeyen Karakterleri Görmek!
Temmuz 30, 2013 § Yorum yok § Kalıcı bağlantı
Dosyamızı oluşturalım:
printf 'testing\012\011\011testing\014\010\012more testing\012\011\000\013\000even more testing\012\011\011\011\012' > /tmp/testing.txt
Dosyanın içeriği
cat /tmp/testing.txt testing testing more testing even more testing
Tab karakterini “^I” olarak görmek için
cat -T /tmp/testing.txt testing ^I^Itesting more testing ^I even more testing ^I^I^I
Satır sonlarını “$” olarak görmek
cat -E /tmp/testing.txt testing$ testing $ more testing$ even more testing$ $
Bütün görünmeyen karakterleri görmek için
cat -A /tmp/testing.txt testing$ ^I^Itesting^L^H$ more testing$ ^I^@^K^@even more testing$ ^I^I^I$
Cat ile dosya oluşturmak
Temmuz 30, 2013 § Yorum yok § Kalıcı bağlantı
# Create file $ cat > /tmp/temp_file_name.txt some content more content and even more content <Ctrl-D> # View file content $ cat /tmp/temp_file_name.txt some content more content and even more content # Append to file $ cat >> /tmp/temp_file_name.txt append content append more content append even more content <Ctrl-D> # View file content $ cat /tmp/temp_file_name.txt some content more content and even more content append content append more content append even more content
Linux versiyon bilgilerini görmek
Temmuz 30, 2013 § Yorum yok § Kalıcı bağlantı
cat /proc/version
dmesg | grep "Linux version"
lsb_release -a LSB Version: :core-4.0-ia32:core-4.0-noarch Distributor ID: Fedora Description: Fedora release 14 (Laughlin) Release: 14 Codename: Laughlin
uname -a
Postgresql’de rastgele sayı oluşturma
Temmuz 30, 2013 § Yorum yok § Kalıcı bağlantı
Postgresql random() fonksiyonu ile 0-1 arasında rastgele sayı döner.
5 tane rastgele sayı dönelim:
SELECT random() FROM generate_series(1,5); random ------------------- 0.595817462075502 0.350072300527245 0.989073566626757 0.700899163261056 0.940509075298905 (5 ROWS)
Rastgele sayıları 1-100 arasına getirelim
SELECT random() * 99 + 1 FROM generate_series(1,5); ?COLUMN? ------------------ 45.0829070857726 96.3123500789516 30.1867960244417 63.0484761050902 44.2645903658122 (5 ROWS)
trunc ile sayıları yuvarlayalım
SELECT trunc(random() * 99 + 1) FROM generate_series(1,5); trunc ------- 21 6 2 57 58 (5 ROWS)
Şimdi bu işleri yapan bir fonksiyon yazalım
CREATE OR REPLACE FUNCTION get_random_number(INTEGER, INTEGER) RETURNS INTEGER AS $$ DECLARE start_int ALIAS FOR $1; end_int ALIAS FOR $2; BEGIN RETURN trunc(random() * (end_int-start_int) + start_int); END; $$ LANGUAGE 'plpgsql' STRICT;
Şimdi deneyelim
SELECT get_random_number(1, 100); get_random_number ------------------- 11 (1 ROW) SELECT get_random_number(45, 46); get_random_number ------------------- 45 (1 ROW) SELECT get_random_number(300, 400); get_random_number ------------------- 372 (1 ROW) SELECT MIN(get_random_number(100, 1000)), MAX(get_random_number(100, 1000)) FROM generate_series(1,100000); MIN | MAX -----+----- 100 | 999 (1 ROW)
Vim Syntax Highlighting Aktivasyonu
Temmuz 30, 2013 § Yorum yok § Kalıcı bağlantı
İlgili “vim-enhanced” paketini kuralım:
yum install vim-enhanced
/etc/profile veya /etc/profile.d/vi-vim.sh veya kullanıcının ~/.bashrc dosyasına alias ekleyelim.
vi .bashrc ... # User specific aliases and functions alias vi=vim
vimrc dosyasını düzenleyelim
vi /etc/vimrc ... syntax on
İşte sonuç:
Not: Vi içinde “:syntax on” ile “:syntax off” bu özellik açılıp kapanabilir.
Yum History Kullanımı
Temmuz 30, 2013 § Yorum yok § Kalıcı bağlantı
Bütün yum işlerini listele
[root ~]> yum history ### OR ### [root ~]> yum history list Loaded plugins: dellsysidplugin2, fastestmirror, refresh-packagekit ID | Login user | Date and time | Action(s) | Altered ------------------------------------------------------------------------------- 45 | System <unset> | 2010-01-18 09:57 | I, U | 21 44 | User <username> | 2010-01-14 15:31 | Install | 1 43 | System <unset> | 2010-01-14 08:13 | Update | 19 42 | System <unset> | 2010-01-13 10:39 | I, U | 40 41 | System <unset> | 2010-01-11 07:59 | Update | 16 40 | System <unset> | 2010-01-08 07:58 | Update | 38 39 | System <unset> | 2010-01-07 08:39 | I, O, U | 39 38 | System <unset> | 2010-01-05 08:23 | O, U | 18 37 | User <username> | 2010-01-04 15:43 | Install | 1 36 | System <unset> | 2010-01-04 07:56 | Update | 66 35 | User <username> | 2009-12-30 10:07 | Install | 2 34 | User <username> | 2009-12-30 10:01 | Update | 15 33 | User <username> | 2009-12-30 08:14 | Install | 13 32 | System <unset> | 2009-12-29 07:52 | I, U | 26 31 | System <unset> | 2009-12-28 08:31 | E, I, U | 66 30 | System <unset> | 2009-12-23 12:11 | Update | 7 29 | System <unset> | 2009-12-22 13:59 | Update | 36 28 | User <username> | 2009-12-21 13:21 | Install | 1 27 | System <unset> | 2009-12-18 14:59 | Update | 56 26 | User <username> | 2009-12-18 08:46 | Install | 1 history list
ID ile history bilgisine ulaşalım:
[root ~]> yum history info 2 Loaded plugins: dellsysidplugin2, fastestmirror, refresh-packagekit Transaction ID : 2 Begin time : Tue Jan 19 15:10:13 2010 Begin rpmdb : 2431:fe4c2c846fd45c9125fb8ab27542a27b22e0d3df End time : 15:10:27 2010 (14 seconds) End rpmdb : 2430:2eeb12b0b0f2ef3fcb31b4447b439e76e92e3866 User : User <username> Return-Code : Success Transaction performed with: Installed rpm-4.7.2-1.fc12.i686 Installed yum-3.2.25-1.fc12.noarch Installed yum-plugin-fastestmirror-1.1.24-2.fc12.noarch Packages Altered: Erase arora-0.10.2-2.fc12.i686 history info
ID ile redo ve undo yapmak
[root ~]> yum history repeat 2 Loaded plugins: dellsysidplugin2, fastestmirror, refresh-packagekit Loading mirror speeds from cached hostfile * fedora: mirror.cogentco.com * livna: rpm.livna.org [...] Repeating transaction 2, from Tue Jan 19 15:10:13 2010 Erase arora-0.10.2-2.fc12.i686 No package matched to remove history repeat [root ~]> yum history undo 2 Loaded plugins: dellsysidplugin2, fastestmirror, refresh-packagekit Loading mirror speeds from cached hostfile [...] Undoing transaction 2, from Tue Jan 19 15:10:13 2010 Erase arora-0.10.2-2.fc12.i686 Resolving Dependencies --> Running transaction check ---> Package arora.i686 0:0.10.2-2.fc12 set to be updated --> Finished Dependency Resolution Dependencies Resolved ================================================================================================================================================================================= Package Arch Version Repository Size ================================================================================================================================================================================= Installing: arora i686 0.10.2-2.fc12 updates 1.1 M Transaction Summary ================================================================================================================================================================================= Install 1 Package(s) Upgrade 0 Package(s) Total download size: 1.1 M Is this ok [y/N]: y Downloading Packages: arora-0.10.2-2.fc12.i686.rpm | 1.1 MB 00:00 [...] Running Transaction Installing : arora-0.10.2-2.fc12.i686 1/1 Installed: arora.i686 0:0.10.2-2.fc12 Complete! [root ~]> yum history redo 2 Loaded plugins: dellsysidplugin2, fastestmirror, refresh-packagekit [...] Repeating transaction 2, from Tue Jan 19 15:10:13 2010 Erase arora-0.10.2-2.fc12.i686 Resolving Dependencies --> Running transaction check ---> Package arora.i686 0:0.10.2-2.fc12 set to be erased --> Finished Dependency Resolution Dependencies Resolved ================================================================================================================================================================================= Package Arch Version Repository Size ================================================================================================================================================================================= Removing: arora i686 0.10.2-2.fc12 installed 3.7 M Transaction Summary ================================================================================================================================================================================= Remove 1 Package(s) Reinstall 0 Package(s) Downgrade 0 Package(s) Is this ok [y/N]: y [...] Running Transaction Erasing : arora-0.10.2-2.fc12.i686 1/1 Removed: arora.i686 0:0.10.2-2.fc12 Complete!
Yum ile tek bir depodan paket kurmak
Temmuz 30, 2013 § Yorum yok § Kalıcı bağlantı
Repoları listeleyelim
$ yum repolist Loaded plugins: dellsysidplugin2, refresh-packagekit repo id repo name status adobe-linux-i386 Adobe Systems Incorporated enabled: 17 fedora Fedora 12 - i386 enabled: 15,366 google Google - i386 enabled: 4 livna rpm.livna.org for 12 - i386 enabled: 3 rpmfusion-free RPM Fusion for Fedora 12 - Free enabled: 383 rpmfusion-free-updates RPM Fusion for Fedora 12 - Free - Updates enabled: 551 rpmfusion-nonfree RPM Fusion for Fedora 12 - Nonfree enabled: 124 rpmfusion-nonfree-updates RPM Fusion for Fedora 12 - Nonfree - Updates enabled: 228 updates Fedora 12 - i386 - Updates enabled: 4,587 repolist: 21,263
Google reposundan paket kuralım
$ yum --disablerepo="*" --enablerepo="google" list available Loaded plugins: dellsysidplugin2, refresh-packagekit Available Packages google-chrome-beta.i386 5.0.307.9-39052 google google-chrome-unstable.i386 5.0.322.2-38810 google google-desktop-linux.i386 1.2.0-0088 google picasa.i386