#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

struct proc_struct {
	pid_t pid;
	unsigned long state;
	/* etc */
};

#define BUF (16*sizeof(struct proc_struct))

int main(void)
{
	int fd, len, i;
	char buf[BUF];

	if ((fd = open("/dev/procsnap", O_RDONLY)) == -1) {
		perror("open");
		exit(EXIT_FAILURE);
	}

	while ((len = read(fd, buf, BUF)) > 0)
		for (i=0; i<len / sizeof(struct proc_struct); i++)
			printf("pid = %d, state = %lu\n",
			       ((struct proc_struct *)buf)[i].pid,
			       ((struct proc_struct *)buf)[i].state);

	if ((fd = close(fd)) == -1) {
		perror("close");
		exit(EXIT_FAILURE);
	}

	exit(EXIT_SUCCESS);
}