semcreate.c

让你了解Unix进程间的通信是如何实现的

#include	"unpipc.h"

int
main(int argc, char **argv)
{
	int		c, flags;
	sem_t	*sem;
	unsigned int	value;

	flags = O_RDWR | O_CREAT;
	value = 1;
	while ( (c = Getopt(argc, argv, "ei:")) != -1) {
		switch (c) {
		case 'e':
			flags |= O_EXCL;
			break;

		case 'i':
			value = atoi(optarg);
			break;
		}
	}
	if (optind != argc - 1)
		err_quit("usage: semcreate [ -e ] [ -i initalvalue ] <name>");

	sem = Sem_open(argv[optind], flags, FILE_MODE, value);

	Sem_close(sem);
	exit(0);
}