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Re: [SG16] A UTF-8 environment specification; an alternative to assuming UTF-8 based on choice of literal encoding

From: Thiago Macieira <thiago_at_[hidden]>
Date: Fri, 30 Jul 2021 07:56:04 -0700
On Thursday, 29 July 2021 19:11:03 PDT Charlie Barto wrote:
> If such functionality were to be added it would be neat if the linux
> implementations worked even if procfs were not mounted (such as when the
> process is init) unless I'm mistaken fetching the command line through proc
> for your own process is making like two system calls to de-reference a
> pointer into your own address space.

Going off-topic here, but correcting the above.
Procfs is not required for one's own command-line and environment in any Unix
I know of. They are duplicated in Linux's /proc, but they are added to the
process' virtual address space just above the stack (and below the auxv).

Trivia: if you modify that area, the /proc files also change, allowing you to
change the name presented in ps and similar tools.

$ ps -o pid,command -Cfile.so
   4873 file.so [kdeinit5] file local:/run/user/1000/klauncherdAEtky.1.slave-
socket local:/run/user/1000/kded5hvkirU.1.slave-socket
   4874 file.so [kdeinit5] file local:/run/user/1000/klauncherdAEtky.1.slave-
socket local:/run/user/1000/kded5FwKgfB.2.slave-socket

Thiago Macieira - thiago (AT) macieira.info - thiago (AT) kde.org
   Software Architect - Intel DPG Cloud Engineering

Received on 2021-07-30 09:56:11