한빛미디어 유닉스시스템프로그래밍 연습문제 2장 4번

oddcat.c

#include <stdio.h>
#include <stdlib.h>
#define BUF_SZB 512
void error(const char *s) {
	printf("%s\n", s);
	exit(EXIT_FAILURE);
}
int main(int argc, char** argv) {
	FILE* from_fp;
	FILE* to_fp;
	char buf[BUF_SZB];
	if (3 != argc) {
		error("Usage: ./oddcat from-file to-file");
	}
	if (NULL == (from_fp = fopen(argv[1], "r"))) {
		error("Could't open from-file for reading");
	}
	if (NULL == (to_fp = fopen(argv[2], "w+"))) {
		error("Could't create to-file for writng");
	}
	while(0 < fread(buf, sizeof(char), 2, from_fp)) {
		fwrite(buf, sizeof(char), 1, to_fp);
	}
	if (-1 == fclose(from_fp)) {
		error("Could't close from-file");
	}
	if (-1 == fclose(to_fp)) {
		error("Could't close to-file");
	}
	return EXIT_SUCCESS;
}