/tmp problem when installing plugins in WordPress

When you try to install a plugin in WordPress and get an error message like this:

Warning: file_exists() [function.file-exists]: open_basedir restriction in effect. File(/tmp//google-integration-toolkit.tmp) is not within the allowed path(s): (/var/www/XXX/) in/var/www/XXX/web/wp-includes/functions.php on line 2140

Warning: touch() [function.touch]: SAFE MODE Restriction in effect. The script whose uid is 12345 is not allowed to access /tmp owned by uid 0 in /var/www/XXX/web/wp-admin/includes/file.php on line 184

Download failed. Could not create Temporary file.

This is happening when the server is running with SAFE MODE because WordPress will not be able to access paths outside it’s web root. Find out the full path to your web root on the server (a hint is in the error message you just saw). Create a temporary directory within your website path and add the following line.

Edit wp-config.php and add:

define(‘WP_TEMP_DIR’, ‘/var/www/XXX/tmp’);

(Replace /var/www/XXX/tmp with the full path to your temporary directory.)

CSS letter-spacing bug in IE7 and solution

A very good and scalable way to set letter spacing in CSS is by using ’em’s as it works relative to the font size. If you for example specify letter-spacing = 0.2em the letter spacing will stay proportional even though you change the font-size. You can easily set the letter spacing for the entire site in all font-sizes.

The ’em’s works exactly like ‘tracking’ which many designers work with. To convert tracking to em just divide it by 1000. That is x em = tracking y / 1000. For example tracking 200 equals to 0.2em.

The definition of 1 em is the size of the character M in the current font size. So 1 em for a font-size of 10px equals to 10px. 1 em for a 24px font size is 24px.

It is very practical to use ’em’s to specify the letter-spacing as it is proportional to the font size. For small ’em’s however, Internet Explorer 7 (IE7) seems to round the values making the letter spacing appear wrong. It works alright in other browsers as well in IE8.

A workaround is to convert the letter spacing to pixels for your current font-size. The drawback is that you have to calculate it for every font-size you are using. And if you change a font-size you must recalculate the letter spacing.

The calculation is really simple. Just multiply the font size in pixels with the letter-spacing in ’em’s and you will get the letter spacing in pixels. If you have a font size of 16 pixels and want a letter spacing of 0.2em (which is equal to a tracking of 200) you do: 16px x 0.2em = 3.2px letter spacing.

Examples using 0.2em (tracking 200):

#mysize16
{
font-size: 16px;
letter-spacing: 3.2px; /* 0.2em x 16px = 3.2px */
}

#mysize24
{
font-size: 24px;
letter-spacing: 4.8px; /* 0.2em x 24px = 4.8px */
}