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krackers/Makefile

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Created September 19, 2023 04:51
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Revisions

  1. @kazupon kazupon revised this gist Oct 5, 2012. 1 changed file with 12 additions and 0 deletions.
    12 changes: 12 additions & 0 deletions Makefile
    View file
    Original file line number Diff line number Diff line change
    @@ -0,0 +1,12 @@
    CC=gcc

    all: multi-process-counter

    build: multi-process-counter

    multi-process-counter:
    ${CC} -std=c99 -o multi-process-counter multi-process-counter.c
    #${CC} -std=c99 -arch x86_64 -o multi-process-counter multi-process-counter.c

    clean:
    rm multi-process-counter
  2. @kazupon kazupon created this gist Oct 5, 2012.
    63 changes: 63 additions & 0 deletions multi-process-counter.c
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    Original file line number Diff line number Diff line change
    @@ -0,0 +1,63 @@
    #include <stdio.h>
    #include <stdlib.h>
    #include <mach/mach_init.h>
    #include <mach/mach_error.h>
    #include <mach/semaphore.h>
    #include <mach/task.h>
    #include <sys/mman.h>
    #include <sys/stat.h>
    #include <sys/types.h>
    #include <fcntl.h>
    #include <unistd.h>

    #define FILE_MODE (S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH)

    /* global */
    semaphore_t mutex;

    int main() {
    int fd, i, nloop, zero = 0;
    int *ptr = NULL;
    nloop = 50000;

    fd = open("./share", O_RDWR | O_CREAT, FILE_MODE);
    write(fd, &zero, sizeof(int));
    ptr = mmap(NULL, sizeof(int), PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
    close(fd);

    printf("ready mmap: %d\n", getpid());

    mach_port_t self = mach_task_self();
    kern_return_t ret = semaphore_create(self, &mutex, SYNC_POLICY_FIFO, 1);
    if (ret != KERN_SUCCESS) {
    fprintf(stderr, "semaphore create failed. Error <%d, %s>", ret, mach_error_string(ret));
    return ret;
    }

    setbuf(stdout, NULL);

    /* child */
    if (fork() == 0) {
    for (i = 0; i < nloop; i++) {
    ret = semaphore_wait(mutex);
    (*ptr)++;
    (*ptr)--;
    (*ptr)++;
    printf("child (%d): %d\n", getpid(), *ptr);
    ret = semaphore_signal(mutex);
    }
    exit(0);
    } else {
    /* parent */
    for (i = 0; i < nloop; i++) {
    ret = semaphore_wait(mutex);
    (*ptr)++;
    (*ptr)--;
    (*ptr)++;
    printf("parent (%d): %d\n", getpid(), *ptr);
    ret = semaphore_signal(mutex);
    }
    }

    return 0;
    }