On Tue, Jun 22, 2010 at 12:35:32PM -0600, Eric Blake wrote:
On 06/22/2010 12:24 PM, Hugh O. Brock wrote:
Correct, we shouldn't change this behaviour - it'll break apps parsing the output
FWIW Rich Jones complains that the output as it stands is nigh on unparseable anyway. Perhaps we should consider that a bug, and fix it...
The new --details option is our chance to change output - it outputs whatever format we want, because it is a new flag; Rich, do you have any preferences about what it _should_ output?
Here's what pool-list --details would currently do, if we applied Justin's patch as-is (modulo no line wrapping added by my email client):
Sorry, been away for a couple of weeks.
virsh # pool-list --details --all Name State Autostart Persistent Capacity Allocation Available --------------------------------------------------------------------------- default running yes yes 1.79 TB 1.49 TB 304.77 GB image_dir running yes yes 1.79 TB 1.49 TB 304.77 GB tmp inactive no yes - - -
One good thing, and several bad things about that. The good thing is that empty columns are presented with '-' which means you can use awk and sort -k to parse the output columnwise. The bad things: * Space within fields "1.79 TB" (awk / sort -k in fact _won't_ work). * Numeric fields aren't numbers: You can't sort -n on "1.79 TB", and you can't read that number into a script and do math on it. Most tools have a "-h" or "--human" option in order to generate human- readable numbers (without spaces), but default to just printing the raw numbers. * Unnecessary "-------" line. * Title line should be optional. Have a --no-title option or something like that to suppress it. * Does virsh still print an unnecessary blank line after the output? If so, stop doing that. Rich. -- Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones New in Fedora 11: Fedora Windows cross-compiler. Compile Windows programs, test, and build Windows installers. Over 70 libraries supprt'd http://fedoraproject.org/wiki/MinGW http://www.annexia.org/fedora_mingw