製作DOS image

http://untitledfinale.wordpress.com/2007/10/09/create-mount-and-copy-floppy-disks-images-under-linux/

Disable Apache folder listing for each folder

1. enable .htaccess file override
edit file /etc/httpd/conf/httpd.conf
search "htaccess", changed below setting to
AllowOverride All

2. go to folder that will disable folder listing
create file .htaccess
add this content:
IndexIgnore *

3. Restart Apache
service httpd restart

Reference:
http://www.cyberciti.biz/faq/apache-web-server-prevent-directory-folder-listing/
http://www.cyberciti.biz/faq/apache-htaccess/

IP address與MAC address的regular expression

IP Address
egrep "^(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?.){3}(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)$"

MAC address
egrep "^([[:xdigit:]]{2}:){5}[[:xdigit:]]{2}$"


http://www.regular-expressions.info/examples.html
http://www.perlmonks.org/?node_id=83405
http://en.wikipedia.org/wiki/Regular_expression

Manipulating Strings

bash下字串的操作

chars="12345678"
echo ${chars:2:3} #234
format: ${string:position:length}
position index從1開始
echo ${chars:2} #345678
從0開始算

reference:
http://tldp.org/LDP/abs/html/string-manipulation.html

bash的array使用方法

參考資料:
[1] bash下array的幾種使用方法

強大的vim

很好很強大的vim
不是打 vi 的廣告， vim 的 search 搜尋功能

add PATH to all user permanently

修改 /etc/profile檔案
pathmunge /usr/local/sbin

參考資料:
http://www.linuxquestions.org/questions/linux-newbie-8/how-to-set-path-how-do-i-set-path-environment-variable-111204/