How MIME contents should be disposed RFC2183

The MIME Content-Disposition: header specifies how a MIME attached file should be handled. The form of the Content-Disposition: header looks like this:

Content-Disposition:  type; parameter=value ...

Here, the value for this header is a sequence of one or more equates, each separated from the others by a semicolon and one or more space or tab characters. The legal parameters are shown in Table 25-13.

Table 25-13. Content-Disposition: parameters


Description of value


The name of the file into which to save the contents. This can be a full path specification. In general, automatically honoring this equate represents a risk.


The original time and date the content was created.


The time and date the content was last modified.


The time and date the content was last read.


The size in bytes of the content.

In general, the Content-Disposition: header should be advisory.

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