limited usability of the library libprocps from an external software

Hello Craig,

the library libprocps exports a limited set of symbols and this, in my
opinion, limits a lot its usability.
A simple PoC follows:

    $ cat procpsng_poc.c
    #include <stdio.h>
    #include <proc/sysinfo.h>

    int
    main ()
    {
      meminfo ();
      printf ("kb_dirty: %lu\n", kb_dirty);
      return 0;
    }

    $ gcc -Wall procpsng_poc.c -o procpsng_poc -lprocps
    /usr/bin/ld: /tmp/cc7MZSOM.o: in function `main':
    procpsng_poc.c:(.text+0x25): undefined reference to `kb_dirty'
    collect2: error: ld returned 1 exit status

Why for instance "kb_main_total" is listed in proc/libprocps.sym but not
"kb_dirty"?

I think several objects declared as extern in proc/sysinfo.h should be
exported too:
  * all the missing kb_* ones,
  * vminfo
  * the vm_nr_* variables.

And maybe other interesting variables declared in the other pubic headers,

What do you think?
Should I open an issue on GitLab? Create a patch?

Take care.
---
Davide Madrisan