micro-utils/coreutils/touch.c

#include <fcntl.h>
#include <unistd.h>
#include <utime.h>
#include <errno.h>
#include <stdio.h>
#include <string.h>
#include <time.h>

int touch(const char *path) {
	int fd = open(path, O_CREAT | O_RDONLY, 0666);
	if (fd < 0) {
		fprintf(stderr, "touch: %s\n", strerror(errno));
		return 1;
	}

	close(fd);

	struct utimbuf new_time;
	time_t now = time(NULL);

	new_time.actime = now;
	new_time.modtime = now;

	if (utime(path, &new_time) < 0)
		return 1;

	return 0;
}

int main(const int argc, const char **argv) {
	if (argc == 1) {
		printf("touch: missing operand\n");
		return 1;
	}

	for (int i = 1; i < argc; i++)
		if (touch(argv[i]))
			return 1;

	return 0;
}