code(alpha) » Tips

CSS3 box-shadow on left and right sides only

Arnaud Soyez — Sat, 25 Jun 2011 21:50:14 +0000

It is possible to have inset shadows on both left and right sides of a block. It is a matter of showing only one side of the box-shadow at a time, and so you need two box-shadows (one for each side of the block you wish to have shadows, and we can put both CSS codes in the same property).

Here is an example that should be compatible with Firefox, Chrome and Opera.

box {
    -moz-box-shadow:
        inset 5px 0 5px -5px #333,
        inset -5px 0 5px -5px #333;
    -webkit-box-shadow:
        inset 5px 0 5px -5px #333,
        inset -5px 0 5px -5px #333;
    box-shadow:
        inset 5px 0 5px -5px #333,
        inset -5px 0 5px -5px #333;
}

Here is the result:

Lorem ipsum...

Inspired from Playing with CSS3 box shadow [demente-design.com]

How to optimize all tables from all databases

Arnaud Soyez — Wed, 06 Oct 2010 00:43:42 +0000

The following command will optimize all of your databases' tables within MySQL.
It is important to optimize tables to reduce data fragmentation.

mysqlcheck -Aop -uroot

If you are not using root replace it with your username.

-A : Check all tables in all databases. This is the same as using the --databases option and naming all the databases on the command line.
-o : optimize the tables.
-p : Prompts for a password to use when connecting to the MySQL server.
-u : The MySQL user name to use when connecting to the server.

Inspired by this article.

Putty and tree - how to avoid weird characters (squares)

Arnaud Soyez — Wed, 15 Sep 2010 10:57:11 +0000

Character encoding is always a problem when communicating between Windows and Linux. And using the "tree" command is affected by this problem if you are connected to a Linux box using Putty on a Windows box. You will certainly get weird characters, probably squares.

For those who are not sure about what tree is. It is a command-line tool to list contents of directories in a tree-like format.

A solution to this problem is to force using plain ASCII characters:

tree --charset=ASCII

You can also have an alias for this command, so that every time you type "tree", it will force tree to use the ASCII charset automatically.

alias tree='tree --charset=ASCII'

And this is an example of what you will get as an output:

/tmp
|-- claws-mail-1000
|-- keyring-x803mg
|   |-- control
|   |-- pkcs11
|   `-- ssh
|-- orbit-gdm [error opening dir]
`-- virtual-user

How to work around "prerequisite RT 0 not found" on Ubuntu

Arnaud Soyez — Sat, 11 Sep 2010 14:19:16 +0000

You installed Request Tracker 3.8 on Ubuntu 10.04 using apt-get, aptitude, or synaptic, and then you needed RT::Authen::ExternalAuth.

What you naturally did is:

sudo cpan -i RT::Authen::ExternalAuth

But you will get the following error:

prerequisite RT 0 not found

This is because you did not install request-tracker through CPAN.

An easy solution for this is to force the installation using the "-f" flag:

sudo cpan -fi RT::Authen::ExternalAuth

How to backup MySQL users except root on Ubuntu

Arnaud Soyez — Sat, 10 Jul 2010 18:24:11 +0000

When you want to backup your mysql databases, you usually do mysqldump ... --all-databases or mysqldump ... --databases mysql ... but you end up with the whole mysql table which is a pain to insert back when you need it because it can mess up the root password or the debian-sys-maint user...

If you wish to just backup all the users and privileges other than root and debian-sys-maint, you can use this command:

mysqldump -nt -uroot -p -w"User NOT LIKE 'root' AND User NOT LIKE 'debian%'" mysql user db > users_privs.sql

Here's an explanation of each of the options:

-nt: Do not add "drop table" and "create table".
-uroot -p: Connect as root and ask for a password
-w...: Add a "WHERE" condition to each query. We exclude everything related to root and debian-sys-maint.
mysql user db: Dump the user and db tables from the mysql database.
> users_privs.sql: Store the sql dump into the users_privs.sql file.