NAME

       sg_get_cpu_stats,                sg_get_cpu_stats_r,                sg_get_cpu_stats_diff,
       sg_get_cpu_stats_diff_between,        sg_get_cpu_percents,         sg_get_cpu_percents_of,
       sg_get_cpu_percents_r, sg_free_cpu_stats - get cpu usage

SYNOPSIS

       #include <statgrab.h>

       sg_cpu_percents *sg_get_cpu_percents (size_t *entries);

       sg_cpu_percents *sg_get_cpu_percents_of (sg_cpu_percent_source cps, size_t *entries);

       sg_cpu_percents *sg_get_cpu_percents_r (const sg_cpu_stats *whereof, size_t *entries);

       void sg_free_cpu_percents (sg_cpu_percents *data);

       sg_cpu_stats *sg_get_cpu_stats (size_t *entries);

       sg_cpu_stats *sg_get_cpu_stats_diff (size_t *entries);

       sg_cpu_stats *sg_get_cpu_stats_r (size_t *entries);

       sg_cpu_stats *sg_get_cpu_stats_diff_between (const sg_cpu_stats *cpu_now, const
                                                   sg_cpu_stats *cpu_last, size_t *entries);

       sg_error sg_free_cpu_stats (sg_cpu_stats *data);

DESCRIPTION

       These are the categories of data delivered by the cpu stats module: sg_get_cpu_stats() and
       sg_get_cpu_stats_r()  deliver  native  cpu  counters  since  the machine has been started,
       sg_get_cpu_stats_diff() and sg_get_cpu_stats_diff_between() deliver  native  cpu  counters
       between     two     sg_get_cpu_stats()     calls    and    sg_get_cpu_percents_of()    and
       sg_get_cpu_percents_r() deliver correlated relative cpu counters (where total is 100%).

       API Shortcut

       ┌──────────────────────────────┬───────────────────┬──────────────────────────┐
       │function                      │ returns           │ data owner               │
       ├──────────────────────────────┼───────────────────┼──────────────────────────┤
       │sg_get_cpu_stats              │ sg_cpu_stats *    │ libstatgrab      (thread │
       │                              │                   │ local)                   │
       ├──────────────────────────────┼───────────────────┼──────────────────────────┤
       │sg_get_cpu_stats_r            │ sg_cpu_stats *    │ caller                   │
       ├──────────────────────────────┼───────────────────┼──────────────────────────┤
       │sg_get_cpu_stats_diff         │ sg_cpu_stats *    │ libstatgrab      (thread │
       │                              │                   │ local)                   │
       ├──────────────────────────────┼───────────────────┼──────────────────────────┤
       │sg_get_cpu_stats_diff_between │ sg_cpu_stats *    │ caller                   │
       ├──────────────────────────────┼───────────────────┼──────────────────────────┤
       │sg_get_cpu_percents_of        │ sg_cpu_percents * │ libstatgrab      (thread │
       │                              │                   │ local)                   │
       ├──────────────────────────────┼───────────────────┼──────────────────────────┤
       │sg_get_cpu_percents_r         │ sg_cpu_percents * │ caller                   │
       └──────────────────────────────┴───────────────────┴──────────────────────────┘
       The    sg_cpu_stats    buffer    received    from     sg_get_cpu_stats_r()     and     the
       sg_get_cpu_stats_diff_between()  as  well  as  the  sg_cpu_percents  buffer  received from
       sg_get_cpu_percents_r()   must    be    freed    using    sg_free_cpu_stats()    or    the
       sg_free_cpu_percents(),  respectively, when not needed any more. The caller is responsible
       for doing it.

       The value stored (the "ticks") will vary between operating systems.  For  example  Solaris
       has  a  total  of  100  per  second,  while  Linux has substantially more. Also, different
       operating systems store different information - you won't find nice  cpu  on  Solaris  for
       example.

       Modern  systems  shall  provide  information  about  the clock tick resolution by invoking
       sysconf(_SC_CLK_TCK).

RETURN VALUES

       There are two structures returned by the CPU statistics functions.

       typedef struct {
               unsigned long long user;
               unsigned long long kernel;
               unsigned long long idle;
               unsigned long long iowait;
               unsigned long long swap;
               unsigned long long nice;
               unsigned long long total;

               unsigned long long context_switches;
               unsigned long long voluntary_context_switches;
               unsigned long long involuntary_context_switches;
               unsigned long long syscalls;
               unsigned long long interrupts;
               unsigned long long soft_interrupts;

               time_t systime;
       } sg_cpu_stats;

       typedef struct {
               double user;
               double kernel;
               double idle;
               double iowait;
               double swap;
               double nice;
               time_t time_taken;
       } sg_cpu_percents;

       user kernel idle iowait swap nice total
              The different CPU states.

       context_switches    voluntary_context_switches    involuntary_context_switches    syscalls
       interrupts soft_interrupts
              The different program actions on CPU.

       systime time_taken
              The time taken in seconds since the last call of the function, or the system time.

SEE ALSO

       statgrab(3)

WEBSITE

       ⟨https://libstatgrab.org/⟩