The OSM FAQ contains the following advice:
"If you can't get your GPX with timestamps with no mean, then you can use this command to fake them:
"Where do I enter this command?"
This is a command entered into a command line interpreter - which is different depending on the Operating System type of your computer.
This FAQ section is probably written with the Linux OS in mind and is just a hint for more advanced users.
It is dependent on the xmlstarlet program being installed first - different procedures for different OS's.
If you're using Windows then running cmd.exe is possible to enable entering the commands, but the example in the FAQ may not work:
I'll reword the FAQ.
answered 10 Apr '12, 00:09
A web search suggests that it's referring to this. You'd enter the command at the command line in whatever operating system that your computer uses, but you'd need to install it first. The documentation suggests that the command might actually be "xml" rather than "xmlstarlet" for the current version.
answered 09 Apr '12, 20:51