mima.c

文件加密的一段程序

#include<stdio.h>
#include<stdlib.h>
void main(int argc,char *argv[])
{
	FILE *fp1,*fp2;
	char c,ch;
	long j;
	if(argc!=3) exit(0);
     fp1=fopen(argv[1],"rb");
	fp2=fopen(argv[2],"wb");
	if(fp1==NULL||fp2==NULL){
        printf("cannot open file\n");
	   exit(1);
	}
	printf(" PLEASE INPUT THE MIMA:");
	scanf("%i",&j);
	srand(j);
	ch=fgetc(fp1);
	while(! feof(fp1)){
	    c=rand();
	    ch=ch^ c;
		fputc(ch,fp2);
		ch=fgetc(fp1);
		}
	 fclose(fp1);
	 fclose(fp2);
	 exit(0);
	 }