On 6/1/2011 4:12 PM, Pádraig Brady wrote:
On 01/06/11 18:11, Rick Stanley wrote:The date command is very useful. A lot of features and options which I take advantage of as I need them. Every once in a while I need to use the command to convert a UNIX Epoch Date to a normal date, so I attempt to use the command as: date -d 1306947372 Which results in the error message, "date: invalid date `1306947372'". Neither 'date --help' or 'man date' shows that the command should have been written as: date -d @1306947372 I needed to do a Google search to see what I was doing wrong. (My memory is not as good as it used to be!) ;^) I don't know why this ('@') is needed, since the date command recognizes many different date formats without specifying the format. For completeness of the help and man page, please add a line explaining that when passing a UNIX Epoch Date to the -d option, you need to prefix the date with a '@'. Thank you for your time and consideration!You need the '@' to disambiguate. Consider fir example: date --date=1243 date --date=@1234 Unfortunately the date input formats are many and varied, and I don't think it's worth getting specific in the man page. The man page currently says: "The date string format is more complex than is easily documented here but is fully described in the info documentation." So I'll close this as adequately documented. thanks, Pádraig.
Jumpin' whale gills! I wish I'd known about the -d @ function! I ended up writing my own in Perl utility just to convert epochs to dates.
I'm with Rick on this one. Date supports so many different date formats without any special arbitrary characters designating the format. The average sys admin just assumes the most simple date format in the world would also work the same way.
Since -d @1234 is so useful, and since it uncharacteristically requires an arbitrary prefix code, I think that it would be a very good to put it in all forms of documentation, even where the dozens of other obvious uses are not documented.
Thanks & have a great day, Jesse Gordon
