linux下用access()判断文件是否存在

代码：

#include <unistd.h>
#include <stdio.h>

/**
 * A example to check the file existence.
 *
 */
int isFileExist(const char* filename) {
	return access(filename, F_OK) == 0;
}

/**
 * Usage: a.out filename
 *
 */
int main(int argc, const char* argv[]) {
	if (argc != 2) {
		printf("Usage: a.out filename\n");
		return 1;
	}

	if (isFileExist(argv[1])) {
		printf("%s exists.\n", argv[1]);
	} else {
		printf("%s does not exist.\n", argv[1]);
	}

	return 0;
}

示例：

~/examples/cpp/access % ./a.out
Usage: a.out filename
~/examples/cpp/access % ./a.out a.out
a.out exists.