Question

I have a class with the following member functions:

 /// caller pid virtual pid_t Pid() const = 0;   /// physical memory size in KB virtual uint64_t Size() const = 0;    /// resident memory for this process virtual uint64_t Rss() const = 0;   /// cpu used by this process virtual double PercentCpu() const = 0;   /// memory used by this process virtual double PercentMemory() const = 0;   /// number of threads in this process virtual int32_t Lwps() const = 0;   

This class’ duty is to return process information about caller. Physical memory size can easily determined by a sysctl call, and pid is trivial, but the remaining calls have eluded me, aside from invoking a popen on ps or top and parsing the output – which isn’t acceptable. Any help would be greatly appreciated.

Requirements:
Compiles on g++ 4.0
No obj-c
OSX 10.5

Answer 1

Process info comes from pidinfo:

cristi:~ diciu$ grep proc_pidinfo /usr/include/libproc.h  int proc_pidinfo(int pid, int flavor, uint64_t arg,  void *buffer, int buffersize); 

cpu load comes from host_statistics:

cristi:~ diciu$ grep -r host_statistics /usr/include/  /usr/include/mach/host_info.h:/* host_statistics() */  /usr/include/mach/mach_host.defs:routine host_statistics(  /usr/include/mach/mach_host.h:/* Routine host_statistics */  /usr/include/mach/mach_host.h:kern_return_t host_statistics 

For more details, check out sources for top and lsof, they are open source (you need to register as an Apple developer but that’s free of charge):

https://opensource.apple.com/source/top/top-111.20.1/libtop.c.auto.html

Later edit: All these interfaces are version specific, so you need to take that into account when writing production code (libproc.h):

/*  * This header file contains private interfaces to obtain process information.  * These interfaces are subject to change in future releases.  */