ExpiresByType
ExpiresByType mime-type time Anywhere, .htaccess when AllowOverride Indexes
ExpiresByType
takes two arguments.
mime-type
specifies a MIME type of file;
time
specifies how long these files are to
remain active. There are two versions of the syntax. The first is
this:
code
seconds
There is no space between code
and
seconds
. code
is one of the following:
A
Access time (or now, in other words)
M
Last modification time of the file
seconds
is simply a number. For example:
A565656
specifies 565,656 seconds after the access time.
The more readable second format is:
base
[plus]number
type
[number
type
...]
where base
is one of the following:
access
Access time
now
Synonym for access
modification
Last modification time of the file
The plus
keyword is optional,
and type
is one of the following:
years
|
months
|
weeks
|
days
|
hours
|
minutes
|
seconds
|
For example:
now plus 1 day 4 hours
does what it says.