ファイル比較プログラム

/*	bmatch.c	Binary Match check program	*/
#include <stdio.h>

void usage(char *prog)
{
	fprintf(stderr, "Usage    : %s  file1  file2\n", prog);
	fprintf(stderr, "Function : Binary Match check program\n");
	exit(0);
}

main(int argc, char *argv[])
{
	FILE *fp1, *fp2;
	char *p1, *p2;
	char buf1[1024], buf2[1024];
	int c1, c2, contflag;
	long count = 0;

	if(argc < 3)	usage(argv[0]);

	fp1 = fopen(argv[1], "rb");
	if(fp1 == NULL)
	{
		fprintf(stderr, "Error : file(%s) can't open.\n", argv[1]);
		exit(-1);
	}

	fp2 = fopen(argv[2], "rb");
	if(fp1 == NULL)
	{
		fprintf(stderr, "Error : file(%s) can't open.\n", argv[1]);
		exit(-1);
	}

	do
	{
		c1 = fread(buf1, sizeof(char), 1024, fp1);
		c2 = fread(buf2, sizeof(char), 1024, fp2);
		contflag = (c1 == 1024) && (c2 == 1024);
		p1 = buf1;
		p2 = buf2;
		while(c1--)
		{
			if(c2-- == 0)	break;
			count++;
			if(*p1++ != *p2++)
			{
				fprintf(stderr, "file1(%s) & file2(%s) not matched at %ld byte.\n",
					argv[1], argv[2], ++count);
				exit(0);
			}
		}
	} while(contflag);
	fprintf(stderr, "file1(%s) & file2(%s) matched in %ld byte.\n",
		argv[1], argv[2], count);
	return 0;
}