The Define Drawing Creation Time function provides information to DWF reading applications about when the .dwf file was generated.

Time The number of seconds elapsed since midnight (00:00:00), January 1, 1970, coordinated universal time (GMT)

Desc Any humanly readable description of the time when the file was generated

Some DWF reading applications may need to "know" when the .dwf file was created. The DWF generating application can indicate this need with the Created opcode:

DWF reading applications should not expect to be able to parse the Desc argument, though it can be shown to a user.

A .dwf file should contain a maximum of one occurrence of the creation time opcode, which by convention should be nested inside a Define Drawing Information Block opcode.

By default no drawing creation time is defined, which is equivalent to

Define Source Drawing Creation Time, Define Drawing Modification Time, Define Source Drawing Modification Time, and Define Drawing Information Block