From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <790bcfc18f41984ae2b80dd2d05f94c3@cat-v.org> To: 9fans@cse.psu.edu Date: Thu, 30 Mar 2006 01:07:30 +0200 From: uriel@cat-v.org In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit Subject: [9fans] Re: patch/list sorry/proc-mtime Topicbox-Message-UUID: 25a098ae-ead1-11e9-9d60-3106f5b1d025 > d-rwxrwxr-x M 430 uriel sys 0 Mar 29 17:43 sorry/proc-mtime > from uriel@cat-v.org > /sys/src/9/port/devproc.c > Make the mtime for files under /proc be the creation time of the process rather than the boot time. > > Wed Mar 29 17:42:05 EST 2006 rsc > This is an interesting idea, but I don't see a use. > The information is already available in /proc/n/status. > Is there a compelling argument to duplicate it? > Being able to ls -lt /proc doesn't count. This has been discussed at length in #plan9, and various people considered it useful, the information is available through /proc/*/status but in a very inconvenient manner. Currently the mtime is the box boot time, which is at best useless and at worst confusing. Knowing when a process was started is extremely convenient, particularly for long-running or broken procs to know which version of a program source they corresponds to. If I make a change to abaco that depends on some new feature of webfs, I'd like to know if I need to restart webfs or not depending on what version is running, or if I find a broken proc and I have been hacking on that program during the last few days, to know roughly what source tree that proc corresponds to. Also from a security perspective it is very useful to know when a program was (re)started in case something fishy is going on. uriel