`readlink -e /proc/$$/exe` would be a simple solution on linux -> /proc is such a fun treasure trove of process info :-)
(Not sure it macOS has as much info in /proc?)
(Not sure it macOS has as much info in /proc?)
macOS does not have procfs
https://en.wikipedia.org/wiki/Procfs
It also got dropped from OpenBSD:
> It was removed from OpenBSD in version 5.7, which was released in May 2015, because it "always suffered from race conditions and is now unused".[2]
The OpenBSD people don't say what you should replace it with, but backing up in the paragraph, the FreeBSD people do:
> As of February 2011, procfs is gradually becoming phased out in FreeBSD.[1]
Chasing that reference:
https://lists.freebsd.org/pipermail/freebsd-fs/2011-February...
> Why is procfs deprecated in favor of procstat?
[snip]
> The security issues are long-standing and there have been many over the years, but the real reason is something that's less evident (or at least less directly apparent):
> Simply put, procfs on FreeBSD has been neglected. There isn't a lot of attention being given to it, and the only modifications in recent months/years have been generally minor compared to the rest of the tree. You can review some of the commits yourself:
> http://www.freebsd.org/cgi/cvsweb.cgi/src/sys/fs/procfs/
> Others like yourself have asked what the state of procfs is, going back as far as 2005. Be sure to read the reply as well:
> http://unix.derkeiler.com/Mailing-Lists/FreeBSD/questions/20...
Here's the FreeBSD procstat manpage:
https://www.freebsd.org/cgi/man.cgi?procstat
Aside from bitrot, is there a reason to prefer procstat over procfs?
/proc is Linux specific, but it's extremely useful. A lot of tools are actually built on top of it, for example ps.
ngarvey@cheapo:~$ strace ps aux |& grep cmdline | head
openat(AT_FDCWD, "/proc/1/cmdline", O_RDONLY) = 6
openat(AT_FDCWD, "/proc/2/cmdline", O_RDONLY) = 6
openat(AT_FDCWD, "/proc/3/cmdline", O_RDONLY) = 6
openat(AT_FDCWD, "/proc/4/cmdline", O_RDONLY) = 6
openat(AT_FDCWD, "/proc/9/cmdline", O_RDONLY) = 6
openat(AT_FDCWD, "/proc/10/cmdline", O_RDONLY) = 6
openat(AT_FDCWD, "/proc/11/cmdline", O_RDONLY) = 6
openat(AT_FDCWD, "/proc/12/cmdline", O_RDONLY) = 6
openat(AT_FDCWD, "/proc/13/cmdline", O_RDONLY) = 6
openat(AT_FDCWD, "/proc/14/cmdline", O_RDONLY) = 6 fish: $$ is not the pid. In fish, please use $fish_pid.
readlink -e /proc/$$/exe
^