unlink_temp.c

来自「LINUX C编程实战这本书附带光盘的原代码」· C语言 代码 · 共 41 行

#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>

/*自定义的错误处理函数*/
void my_err(const char * err_string, int line)
{
	fprintf(stderr, "line:%d  ", line);
	perror(err_string);
	exit(1);
}

int main()
{
	int	fd;
	char	buf[32];

	if ((fd = open("temp", O_RDWR|O_CREAT|O_TRUNC, S_IRWXU)) < 0) {
		my_err("open", __LINE__);
	}
	if (unlink("temp") < 0) {
		my_err("unlink", __LINE__);
	}
	printf("file unlinked\n");

	if (write(fd, "temp", 5) < 0) {
		my_err("write", __LINE__);
	}
	if ((lseek(fd, 0, SEEK_SET)) == -1) {
		my_err("lseek", __LINE__);
	}
	if (read(fd, buf, 5) < 0) {
		my_err("read", __LINE__);
	}
	printf("%s\n", buf);
	
	return 0;
}