C Find current process rss

[lukesky21]

In a C/C++ program I need to find the current process's rss memory usage. In Linux I can get that from /proc/PID/statm but /proc doesn't exist in FreeBSD. I looked at getrusage(2) but that looks to only return the maximum RSS of the process which is not what I need.
Are there any ways to get that information in FreeBSD?

 

[SirDice]

In Linux I can get that from /proc/PID/statm but /proc doesn't exist in FreeBSD.

/proc does exist; procfs(5). It's not required or enabled by default, nothing from the base OS relies on it.

 

[lukesky21]

I understand that and I would rather not enable the proc file system. I would like to be able to pull the current process RSS directly from a C/C++ API. Is that possible?

 

[SirDice]

I'm fairly certain it's possible, but I'm not much of a programmer. You could have a look at the source code from top(1) to see how it's done there?

top « usr.bin - src - FreeBSD source tree

cgit.freebsd.org

 

[covacat]

look at ps(1) source code
kvm_getprocs, etc

 

[lukesky21]

I think I may have found the answer - kinfo_getproc(3)

 

[mark_j]

If you're getting into accessing system information, then also take the time to learn sysctl(3). As the man page for kinfo_getproc(3) says, it's just a wrapper for sysctl(3) for a specific set of MIBs.