Thanks Greg. Good to know that. regards.
On Sat, Feb 18, 2023 at 9:08 AM Greg Wooledge <g...@wooledge.org> wrote: > On Sat, Feb 18, 2023 at 08:38:22AM +0800, winnie hw wrote: > > sorry this is maybe not related to debian directly. > > but how can I compare two versions of a package by programming? > > for instance, v1.24.0.1 should be later than v1.23.99.999. > > Debian's dpkg(1) command has a --compare-versions option. > > --compare-versions ver1 op ver2 > Compare version numbers, where op is a binary operator. dpkg > returns true (0) if the specified condition is satisfied, and > false > (1) otherwise. > > unicorn:~$ if dpkg --compare-versions v1.24.0.1 gt v1.23.99.999; then echo > true; else echo false; fi > dpkg: warning: version 'v1.24.0.1' has bad syntax: version number does not > start with digit > dpkg: warning: version 'v1.23.99.999' has bad syntax: version number does > not start with digit > true > > I wonder if those were the actual version numbers you intended to compare. > Also, your example isn't particularly good, because a simple string > comparison also would have returned true in this case, even though it's > entirely the wrong approach. > > A better example would be something like: > > unicorn:~$ if dpkg --compare-versions 1.24.0.1 gt 1.9.99.999; then echo > true; else echo false; fi > true > > because a string comparison gives a different result here. > > Also, you might be interested in the -V option of GNU sort(1). It > purports to do some kind of version string comparison. I have no idea > whether it handles all the possible Debian versions strings the same > way that dpkg --compare-versions does. > >
