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).

The source code file is copyright 2022, Michael Kerrisk, and is licensed under the GNU Lesser General Public License, version 3.

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.


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

/* 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"
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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