procres/print_rusage.c

This is procres/print_rusage.c, an example to accompany the book, The Linux Programming Interface.

This file is not printed in the book; it is the solution to Exercise 36-2:b (page 765).

In the listing below, the names of Linux system calls and C library functions are hyperlinked to manual pages from the Linux man-pages project, and the names of functions implemented in the book are hyperlinked to the implementations of those functions.

Download procres/print_rusage.c

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Function list (Bold in this list means a function is not static)

printRusage()

/* print_rusage.c

   Print the contents of an 'rusage' (resource usage) structure
   (returned by a call to getrusage()).
*/
#include <sys/resource.h>
#include "print_rusage.h"
#include "tlpi_hdr.h"

void
printRusage(const char *leader, const struct rusage *ru)
{
    const char *ldr = (leader == NULL) ? "" : leader;

    printf("%sCPU time (secs):         user=%.3f; system=%.3f\n", ldr,
            ru->ru_utime.tv_sec + ru->ru_utime.tv_usec / 1000000.0,
            ru->ru_stime.tv_sec + ru->ru_stime.tv_usec / 1000000.0);
    printf("%sMax resident set size:   %ld\n", ldr, ru->ru_maxrss);
    printf("%sIntegral shared memory:  %ld\n", ldr, ru->ru_ixrss);
    printf("%sIntegral unshared data:  %ld\n", ldr, ru->ru_idrss);
    printf("%sIntegral unshared stack: %ld\n", ldr, ru->ru_isrss);
    printf("%sPage reclaims:           %ld\n", ldr, ru->ru_minflt);
    printf("%sPage faults:             %ld\n", ldr, ru->ru_majflt);
    printf("%sSwaps:                   %ld\n", ldr, ru->ru_nswap);
    printf("%sBlock I/Os:              input=%ld; output=%ld\n",
            ldr, ru->ru_inblock, ru->ru_oublock);
    printf("%sSignals received:        %ld\n", ldr, ru->ru_nsignals);
    printf("%sIPC messages:            sent=%ld; received=%ld\n",
            ldr, ru->ru_msgsnd, ru->ru_msgrcv);
    printf("%sContext switches:        voluntary=%ld; "
            "involuntary=%ld\n", ldr, ru->ru_nvcsw, ru->ru_nivcsw);
}

Download procres/print_rusage.c

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