Sergey Poznyakoff <[EMAIL PROTECTED]> writes: > What's the exact reason for this change: > >> The -v option now prints time stamps only to 1-minute resolution. > > It breaks backward compatibility, is it really needed?
It's not essential, but I think it's an improvement. Here's the background. Traditional tar -tv (and GNU tar up through 1.11) prints time stamps only to 1-minute resolution, so to some extent this might be called reverting to tradition. When GNU tar -tv started producing ISO-style time stamps (circa 1997), it also started printing the seconds, as this presents the full timestamp information to the user. When I improved the support for nanosecond timestamps yesterday, I initially follwed in that precedent by outputting the full resolution time stamp. But the output got too long. For example, instead of seeing this: -rw-rw-r-- eggert/faculty 3669 2005-04-18 11:40:26 provider/GnuRSAPublicKey.java I started seeing this: -rw-rw-r-- eggert/faculty 3669 2005-04-18 11:40:26.327960193 provider/GnuRSAPublicKey.java Furthermore, if tar outputs this extra time stamp information, it runs into the problem that some timestamps are wider than others, and it has to adjust the time stamp print width on the fly, causing ragged columns in some cases and excess white space in others. So the output might end up looking like this: -rw-rw-r-- eggert/faculty 345 2005-04-18 11:40:24 provider/BasicInfo.java -rw-rw-r-- eggert/faculty 3669 2005-04-18 11:40:26.327960193 provider/GnuRSAPublicKey.java -rw-rw-r-- eggert/faculty 69 2005-04-18 11:40:27 provider/LongWinded.java or, if you always output nanoseconds, like this: -rw-rw-r-- eggert/faculty 345 2005-04-18 11:40:24.000000000 provider/BasicInfo.java -rw-rw-r-- eggert/faculty 3669 2005-04-18 11:40:26.327960193 provider/GnuRSAPublicKey.java -rw-rw-r-- eggert/faculty 69 2005-04-18 11:40:27.000000000 provider/LongWinded.java Given all these problems, I thought it better to go back to the older tradition and output time only to the nearest minute (albeit with ISO 8601 format rather than Unix Version 7 format): -rw-rw-r-- eggert/faculty 345 2005-04-18 11:40 provider/BasicInfo.java -rw-rw-r-- eggert/faculty 3669 2005-04-18 11:40 provider/GnuRSAPublicKey.java -rw-rw-r-- eggert/faculty 69 2005-04-18 11:40 provider/LongWinded.java under the argument that this is enough time stamp information for ordinary use. If you prefer outputting full time information instead, I can easily generate it. But I think it'd be better to do it as an option. Perhaps we could add a --full-time option, which acts like GNU ls's --full-time output, and causes it to output the nanoseconds. Even fancier would be to add GNU ls's --time-style option, which would let the user specify an arbitrary strftime format. _______________________________________________ Bug-tar mailing list [email protected] http://lists.gnu.org/mailman/listinfo/bug-tar
